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Feasibility and Viability of Landfill Mining

and Reclamation in Scotland

Scoping Study

Final Report April 2013

Zero Waste Scotland works with

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and local authorities to help them

reduce waste, recycle more and use

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Written by: Simon Ford, Kathryn Warren, Carrie Lorton, Richard

Smithers, Adam Read and Mark Hudgins.

http://www.zerowastescotland.org.uk/

Feasibility and Viability of Landfill Mining and Reclamation in Scotland

Executive Summary

Introduction

This scoping study was undertaken by Ricardo-AEA on behalf of Zero Waste Scotland (ZWS) in the

period August 2012 to April 2013. The study was commissioned to assist ZWS and the Scottish

Government in the feasibility assessment of the potential for the mining and reclamation of materials

from landfill sites in Scotland. The study considers the potential to mine and reclaim materials from

Scottish landfills in general, but also gives particular consideration to the potential to reclaim materials

from the oil-shale spoil heaps (bings) in West Lothian. No documented landfill mining has taken place

in Scotland to date, although some reclamation of material from its bings has been undertaken,

including within West Lothian.

The study comprised three main elements:

1 A full review of the history of Landfill Mining and Reclamation (LFMR) and documented

examples of practice both in the UK and worldwide.

2 A full review and evaluation of all economic, technical, environmental, regulatory and

sociological issues associated with the feasibility and viability of LFMR in Scotland and

including the ecological factors specifically related to the oil-shale bings located in West Lothian.

3 Conclusions and recommendations regarding the feasibility and viability for LFMR activities in

Scotland, including the oil-shale bings in West Lothian.

Background

The first LFMR project took place in Israel in 1953. Since then, in excess of 60 worldwide projects are

reported in literature. This is a small number given the amount of landfills in existence around the

world. Most of these projects have been undertaken for drivers other than resource and energy

recovery, including moving waste to make way for development, voidspace recovery, pollution

mitigation and bringing the landfill lining up to required standards.

One LFMR project that is of particular interest is the Advanced Plasma Power (APP)/Group Machiels

project at the Remo landfill in Belgium. This project is yet to commence, but will be the first full-scale

project of its kind and it is being undertaken primarily for resource/energy recovery purposes. This is

a modern-day project, with resource and energy recovery, that is likely to inform future LFMR

projects.

General Findings

Overall, the findings of this study indicate that LFMR operations could potentially be feasible in

Scotland but viability is likely to be limited to very specific circumstances. The planning and

undertaking of a LFMR project in Scotland, undertaken with resource recovery in mind, will be a

complex operation. The authors consider that it is unlikely to become a widespread occurrence in the

near future, principally due to economic viability but also as a result of the technical challenges

associated with this type of operation. A discusson of the key factors associated with project feasibility

is provided below.


Technical

LFMR operations have been undertaken in various parts of the world, including in the UK. Provided

that adequate controls are in place, including proper assessment of gas risk issues, landfill materials

can be excavated using conventional excavators and associated plant. Materials recovery operations

associated with LFMR activities undertaken to-date have primarily comprised soil and metals removal,

and, on occasion, the preparation of a refused derived fuel and the replacement and compaction of

residual materials back in the landfill.

It is expected that applying advanced waste separation technologies to landfilled waste will give rise

to previously unseen challenges associated with separation efficiency, breakdown, blockage and high

maintenance costs. Furthermore, the use of conventional waste separation techologies to extract

certain materials (e.g. plastics) or provide greater levels of refinement is likely to be very difficult due

to the differences between regular municipal solid waste streams and the nature of excavated

landfilled materials (e.g. greater levels of compaction and intermingling).

The soil and rubble/hardcore materials recovered is likely to be limited to use onsite, as end of waste

criteria and the quality of these materials are likely to prevent them being used away from the site

where they were extracted.

Economic

Economic viability for any specific LFMR project will be subject to a wide range of variables, the key

ones being capital and operational costs, the value of materials extracted from the waste (e.g. metals

and refuse derived fuel), and cost and/or availability of a suitable outlet for recovered soils and

refused derived fuel (if appropriate). Waste quantity and composition are critical as these will

determine the economy of scale and potential revenues associated with the operation. In terms of

composition, waste from the mid 1960’s to the mid 1990’s is likely to yield the most valuable materials

as this corresponds to a period of increased disposal of potential valuable materials and predates

widespread recycling activities in the UK.

As part of the study, Ricardo-AEA developed a simple economic model to allow the comparative

assessment of several different types of LFMR project. The outputs of the modelling indicated that

LFMR is unlikely, in most situations, to be economically self-sufficient. However there are, potentially,

some situations where LFMR operations could be economically viable. These are:

Feasibility

Regulatory, environmental

and social

Economic

Technical


1 LFMR involving onsite energy recovery at non-hazardous landfills where the waste being mined

has stabilised (e.g. generating reduced quantities of gas and lower strength leachate). Where

landfilling has taken place in unconnected engineered cells, it is possible that LFMR could be

undertaken at discreet cells on active landfills that have been in operation for a long time. Due to

the capital costs associated with construction of small-scale thermal treatment plants, the

economic viability of this type of LFMR is likely to be better at Scotland’s larger landfills.

2 Excavation, shredding, screening and removal of ferrous metal, with sale of metal, recovery of soil

for use as daily cover and replacement and compaction of waste may be economically viable

based on the voidspace recovered. As the processing equipment used for such an operation is

typically mobile and can be leased, this could potentially be carried out on any size of landfill. This

scenario has not been assessed in this study, which has focused on maximum utilisation of

recoverable material. However, this has been undertaken at landfills in the USA with some

reported success.

3 LFMR with resource and off-site energy recovery might be feasible where wastes are to be

excavated anyway, assuming that the alternative is to pay for landfill elsewhere. This is not likely

to be commonplace and restricted to situations where waste is being excavated in order to

relocate it. Even though the LFMR operation may not be economically viable in its own right, the

recovery of soil for use as daily cover, the recovery of metals, and possibly lower gate fees for

thermal treatment of RDF as opposed to landfill, may help to offset some costs associated with

the relocation exercise.

Local environmental and sociological factors

In terms of environmental and sociological factors, LFMR has the potential to create significant local

environmental impact, health and safety risk and nuisance risk. While mitigation measures can be put

in place, the cost of doing so could be prohibitive for some potential projects. These issues will need

to be considered on a project-by-project basis.

Positive benefits may also result, in particular resulting from removal of a potential source of pollution,

with benefit to the local environment and potential positive opinion from local stakeholders.

Furthermore, a LFMR project will create green jobs.

Regulatory issues

In terms of regulatory requirements, a LFMR will require appropriate authorisation which is likely to

include the need for planning approvals and environmental permits. Clearly, these issues can ony be

considered on a project-by-project basis but, overall, there are no generic regulatory barriers to LFMR.

Assessment of the Potential to Mine and Reclaim Materials from Bings

In relation to the feasibility and viability of extraction and recovery of materials from the bings of West

Lothian, the main conclusions of this study are listed below.

Recent extraction of material from oil-shale bings demonstrates that the recovery of material for

use in construction applications is both technically and economically feasible. The economic

feasibility depends on distance between the bing and point of use, and it is unlikely that the bing

material would be used other than in areas in proximity to West Lothian.

Whilst the aggregate material does have some advantages in particular applications, it is generally

used as low grade fill material, of which there are numerous other sources, both virgin and

secondary, in the wider area and the rest of Scotland.

A review of the ecological issues associated with the bings has demonstrated the ecological

importance of the bings, due to the unique and diverse habitats that they provide. There are

undisputable ecological benefits as a result of leaving specific bings untouched.


The environmental impacts of extracting bing material will be localised, but could be significant for

local communities. Similarly, the sociological impacts of working or removing the bings will also

impact locally, on communities who have come to accept the bings as a permanent and important

feature of their local landscape.

West Lothian Council has categorised the bings to determine which bings have the most potential

for extraction of materials. Out of the 19 remaining bings in West Lothian, only four have existing

planning permission with extraction being encouraged. There are a further three at which

extraction may be encouraged, but which do not currently have planning permission. The

remaining bings are either restored, protected or have already been exhausted of materials.

Therefore the actual potential for extracting materials from the bings may be smaller than initially

expected. The fact that the council have stated that they will resist extraction proposals for bings

which remain fully intact suggest that the ecological and social importance of these sites has been

recognised.

In conclusion, whilst there are some useful materials which could readily and economically be

extracted from the bings, the ecological, environmental and sociological impacts on local communities

will be significant, and will need to be considered on a case by case basis.

Recommendations

As a next step, it is recommended that this study is shared with interested parties. As well as

regulators and policy makers, this should include landfill operators and companies that may be

interested in being involved in a LFMR project in Scotland. If ZWS and the SG wish to further

investigate the undertaking of LFMR in Scotland, the insight and opinions of such stakeholders will

undoubtedly add to the understanding of the feasibility and viability of LFMR in Scotland.

If ZWS, the SG, or any other stakeholder is interested in pursuing the possibility of LFMR in Scotland,

it will be necessary to undertake a screening exercise to identify suitable landfills, and then to

undertake a detailed feasibility and viability study for a specific landfill. The screening exercise would

require access to a greater level of data than reviewed for this scoping study. Following the screening

exercise, it would of course be necessary to first establish operator interest. A screening exercise may

not be necessary if a landfill operator comes forward with a suitable landfill and a keen desire to

establish feasibility and viability of LFMR for that specific site.

In removing organic wastes from the landfill in a LFMR project, the absence of gas generation and

fugitive emission will benefit the UK’s greenhouse gas emissions targets under the Kyoto Protocol and

potentially any credits gained for the avoidance of fugitive emissions could positively impact upon

LFMR project economics. The economic assessment presented in this study has not considered

incentives/credits for avoidance of fugitive emissions of landfill gas. It is, however, recommended that

consideration is given to this matter, in particular in relation to any possible future detailed site

specific feasibility assessment, as well as at a national policy level. In particular, consideration should

be given to whether a LFMR project in Scotland could qualify for Emission Reduction Units (ERUs)

under the Joint Implementation (JI) mechanism.

Whilst detailed composition analysis would be required in the development of a specific LFMR project

on a specific landfill, there would be merit in better understanding the waste in Scotlands landfills at a

higher level. This would require trial pitting and sorting and analysis on landfilled waste of known age

and waste type at a number of landfills. This will further inform assessment of feasibility of LFMR in

Scotland. In undertaking the composition exercise, it would be useful to undertake detailed analysis of

specific wastes, e.g. in addition to having a category for small WEEE, that small WEEE could be

further broken down into type and material content. In-turn, this could inform a study into the

feasibility of the recovery of certain high value metals which, if not feasible now, might be feasible in

a future of increased resource scarcity.


On-site energy recovery is a strong factor influencing financial viability of LFMR. Whilst financial

viability is currently borderline at best, it would be useful to undertake an assessment of energy

market trend to ascertain whether at some point in the future it is likely that energy from landfilled

waste (EfLFW) will be viable in its own right.

Finally, this study has highlighted the importance of understanding the waste present in a landfill to

LFMR and how this understanding is generally poor for historically landfilled waste. It is recommended

that consideration is given to methods of improving this situation going forward, e.g. what measures

can be taken to ensure operators record which wastes are placed where in a landfill and when.

Further to informing future potential LFMR, this will also assist those undertaking detailed modelling of

landfill gas and leachate and the undertaking of environmental risk assessments.


Contents

1 Background 1

1.1 Objectives 1

1.2 Scotland’s Landfills 2 1.2.1 Numbers and types of landfills 2 1.2.2 Waste composition 3

1.3 Oil Shale Bings of West Lothian 7

2 Landfill Mining and Reclamation Feasibility and Evaluation 8

2.1 Historic and current LFMR projects worldwide 8 2.1.1 History of LFMR 8 2.1.2 Case studies 9 2.1.3 Feasibility studies undertaken elsewhere 12

2.2 Implications of worldwide experience to landfill mining in Scotland 13

2.3 Evaluation of issues (Scotland) 15 2.3.1 A ‘typical’ Scottish landfill 15 2.3.2 Overview of economic issues 19 2.3.3 Economic issues specific to Scotland 21 2.3.4 Economic analysis of a hypothetical Scottish LFMR project 28 2.3.5 Summary of economic implications of landfill mining in Scotland 32 2.3.6 Technical issues 33 2.3.7 Environmental issues 39 2.3.8 Regulatory issues 43 2.3.9 Sociological issues 46

2.4 Conclusions 48

2.5 Recommendations 50

3 Feasibility and Evaluation of Oil Shale Bing Resource Reclamation 52

3.1 Overview 52

3.2 Evaluation of issues 52 3.2.1 Technical issues 52 3.2.2 Economic issues 53 3.2.3 Environmental issues 54 3.2.4 Regulatory issues 55 3.2.5 Sociological issues 56 3.2.6 Ecological value 56

3.3 Conclusions 63

References

Appendices Appendix 1: Scotland’s licensed/permitted landfills (in use- 2010)

Appendix 2: Scotland’s licensed/permitted landfills (closed- 2010)

Appendix 3: Summary of selected SEPA data on Scotland’s landfills

Appendix 4: Worldwide historic and current LFMR projects and drivers

Appendix 5: Economic model

Feasibility and Viability of Landfill Mining and Reclamation in Scotland 1

1 Background

1.1 Objectives

The Scottish Government (SG) and Zero Waste Scotland (ZWS) are keen to investigate the feasibility

and viability of mining and reclamation of materials from landfill sites throughout Scotland, including

the oil-shale heaps (bings) in West Lothian. The bings comprise wastes from the historic processing,

to produce oil, of Scotland’s oil shale deposits. No documented landfill mining has taken place in

Scotland to date, although some reclamation of material from its bings has taken place, including

those within West Lothian.

The SG and ZWS are particularly interested in assessing the potential for extraction of materials from

landfills for resource reuse, recycling and energy recovery. Materials could typically include, metals,

plastics, organics, aggregates and soils. This is against a backdrop of increasing material and fuel

resource scarcity and a drive towards increased sustainability. Use of local and dormant resources

could contribute to the reduction of virgin raw material consumption in Scotland.

Both the SG and ZWS recognise that Landfill Mining and Reclamation (LFMR) could bring additional

benefits such as landfill voidspace recovery, freeing-up land for redevelopment, and reduction or

elimination of costs associated with landfill aftercare and environmental remediation. Landfill mining

could increase the land value and allow future use of closed landfill sites for the development of

housing, recreational or industrial use. Whilst development on old gassing landfills has taken place in

the past, including housing development, it has brought with it certain problems and risks.

Development on, or near, landfill is now highly regulated and development on landfill largely consists

of development of other waste treatment facilities. The application of LFMR could both avoid long-

term costs and bring forward the point at which a site could be used for new development.

For decades, landfilling of waste was the principle means of waste disposal both in Scotland and the

rest of the UK. In more recent times, environmental, economic and regulatory drivers have led to the

introduction of alternatives to landfill and Scotland is a pioneer in driving waste up the waste

hierarchy and introducing new legislation to further divert recyclable materials away from its landfills

and from incineration. Despite continuing increases in recycling and landfill diversion, landfill still

remains part of the waste solution in Scotland. At some point in the future, available existing landfill

voidspace will run out, giving rise to a need to develop new landfills or to recover voidspace at

existing sites.

Faced with these issues, LFMR may seem at face value a viable option to undertake in Scotland,

however the implications surrounding this activity are not fully understood. Issues including technical,

economic, environmental, regulatory and sociological impacts will need to be assessed.

This high level scoping study was commissioned by ZWS to focus on three specific areas:

1 A full review of the history of LFMR and documented examples of practice both in the UK and

worldwide;

2 A full review and evaluation of all economic, technical, regulatory and sociological issues

associated with the feasibility and viability of LFMR in Scotland and including the ecological factors

specifically related to the oil-shale bings located in West Lothian; and

3 Conclusions and possible recommendations regarding the feasibility and viability for LFMR

activities in Scotland including the oil-shale bings in West Lothian.

2 Feasibility and Viability of Landfill Mining and Reclamation in Scotland

1.2 Scotland’s Landfills

1.2.1 Numbers and types of landfills

Scotland’s landfills are best described by reference to sites with licences or permits, which are

regulated by the Scottish Environment Protection Agency (SEPA). This captures the bulk of landfills

likely to be of interest to this study. Landfills that are not currently licenced or permitted will include:

Illegal landfills.

Very old landfills that pre-date modern waste licensing and permitting regimes.

Very small inert landfills.

Sites which previously held a licence or permit, which has now been surrendered as the landfill was

proven to no longer pose a risk to the environment.

Very old landfills may be subject to regulation under the contaminated land regime, although such

sites are not included in the discussion here.

Landfills that have surrendered their permit are not likely to be non-hazardous landfills as most non-

hazardous landfills in Scotland contain biodegradable waste and, upon closing, are likely to take many

decades to stabilise to the extent that permit surrender is acceptable to the regulator, SEPA.

Surrender criteria is likely to be easier to achieve at inert landfills, and so the probablity is that a

landfill that has surrendered its permit will be an inert landfill.

Records of Scotland’s landfills that are regulated through licences or permits are available on SEPA’s

website. The most recent data available refers to the year 2010. There are two key data sets with

corresponding reports.

Landfill sites and capacity report for Scotland 2010.

Waste sites and capacity report for Scotland 2010.

The latter report and corresponding data set includes landfills as well as other facilities.

Appendix 1 and Appendix 2 contain SEPA maps showing the location of operational and closed landfills

in Scotland in 2010. Pertinent information from the SEPA 2010 data describing the numbers and types

of landfills has been summarised in a table in Appendix 3.

To be an operational landfill in the present day means that the landfill has submitted a PPC Permit

application, the landfill was deemed to meet the criteria required by the Landfill Directive, and SEPA

issued a PPC Permit.

Non-operational landfills are more likely to be considered for landfill mining owing to their age and,

therefore, reduced methane production. However, operational landfills with distinct engineered

separate cells may contain cells that are of sufficient age to make them potential candidates for LFMR.

These would tend to be larger landfills that have been operational for many years. Not all landfill

operations are undertaken with distinct multiple cells.

Non-operational landfills are more likely to be variable in containment quality and provision of gas and

leachate control and are more likely to contain unknown waste types and volumes. This is because

the regulation of older landfills was less onerous than in the current day and record keeping was

generally poor prior to the requirement to submit waste return data to the regulator.


Considering landfills by status, classification and waste type, landfills not considered likely contenders

for LFMR projects are discussed below.

It is possible that some of the inert waste only sites could contain materials worthy of recovery.

However, if this is the case it would apply to a very limited amount of landfills. Most inert landfills

primarily receive soils and rubble from numerous sources. Reuse of this material for engineering

purposes would be limited by variable quality and end of waste criteria. Much of the inert waste

landfilled in inert waste only landfills would have been landfilled prior to current day stringent

waste acceptance criteria. Inert landfills are not considered worthy candidates for further

consideration in this high level nationwide study owing to the inability to adequately assess waste

type and the low level, if any, potential for beneficial reuse or recovery.

Hazardous waste only sites are not worthy of consideration due to their limited number and nature

of the waste landfilled. There is one operational hazardous waste landfill and one closed special

waste (now known as hazardous waste) landfill in Scotland.

Many closed landfills no longer subject to regulation by licence or permit are expected to be inert

sites, given the operators associated with them and the fact that the permit has been surrendered.

This will not exclusively be the case and some of these landfills will be potential candidates.

However, the readily available data on these sites is very limited.

With the above considerations, it is considered that non-hazardous landfills are likely to be the best

candidates for landfill mining and these are the landfills considered in this study. From review of the

2010 SEPA data, this comprises:

48 operational landfills

2 landfills that were being restored in 2010

168 closed landfills still subject to regulation

An unknown number of closed landfills that have surrendered their licences. However, these are

not considered in this study owing to a lack of readily available data. These are not expected to be

many in number as it is suspected that many of the 100 landfills in this category are inert landfills.

1.2.2 Waste composition

At a high level, e.g. inert/non-hazardous/hazardous or household, commercial, industrial etcetera,

information on waste landfilled in Scotland is detailed in the table in Appendix 3. However, in order to

assess the viability of LFMR in Scotland it is necessary to further characterise the waste present in

Scotland’s landfills. There are many difficulties associated with doing this, in particular because there

have been no known studies where landfilled waste in Scotland has been excavated for composition

analysis. In addition, prior to the requirement to submit waste returns to the regulator, there was no

requirement to maintain detailed records of wastes accepted at landfills. Even where records are kept,

these refer to waste source and type and not detailed constituent composition.

Characterising the waste in Scottish landfills could be undertaken by looking at the composition of

waste at the point the material became a waste, e.g. reviewing studies of waste composition analysis

at the point of generation. This approach, whilst specific to Scotland or the UK, also has limitations.

Such studies are limited and have only been undertaken in recent times as segregated waste

collections have been introduced and alternative waste management facilities have been developed.

These studies represent notably different waste streams to those traditionally landfilled in previous

decades. Most pertinent of all is the fact that waste composition in a landfill will change over time as

waste degrades. It is necessary to establish likely composition in the present day rather than at the

point in time the waste was deposited in the landfill.

Given the absence of data on waste composition in Scottish landfills and the issues associated with

looking at waste composition at the point of generation, the most reliable way of establishing likely


landfill composition is to review findings of studies undertaken elsewhere. Whilst this is appropriate for

this high level national study, detailed desk study and intrusive investigation and analysis would be

required prior to undertaking a LFMR project at a specific individual landfill.

From a review of literature, the most relevant information on composition of landfilled wastes is

presented in a paper titled ‘Feasibility study sustainable material and energy recovery from landfills in

Europe’ (W.J. Van Vossen and O.J. Prent, 2011). The authors reviewed 60 landfill mining projects and,

where composition information was available, determined average waste composition to be as

detailed in Table 1.1 below.

Table 1.1 Typical composition of excavated waste (W.J. Van Vossen and O.J. Prent, 2011)

Waste Average waste composition

(incl. soil) (%)

Average waste

composition (excl. soil)

(%)

Plastic 4.6 10.3

Paper and cardboard (P&C) 5.3 11.8

Glass 1.1 2.5

Total metals (T-metals) 2.0 (1.7% ferrous, 0.1%

aluminium, 0.1% non-ferrous)

4.1 (3.7% ferrous, 0.3%

aluminium, 0.2% non-

ferrous)

Organic 5.3 11.6

Wood 3.6 8.0

Leather 1.6 3.5

Textile 1.6 3.6

Construction and demolition waste

(CDW)

9.0 19.9

Stones 2.5 5.5

Other 5.8 12.8

Non-MSW 0.3 0.8

Soil (diameter less than 24mm) 54.8 0.0

Inert 2.6 5.8


The authors of the paper describe a ‘standard landfill’ as having the composition in the table above, a

capacity of 500,000 tonnes and surface area of 5 ha. The authors note the composition will not be

accurate in all cases.

In a presentation by Joakim Krook of Linkoping University (Sweden), composition of landfilled waste

from two Swedish landfills, seven USA landfills, one Korean landfill, one Italian landfill and one

German landfill is presented. Typical composition presented is detailed in Table 1.2.

Table 1.2 Typical composition of excavated waste (from a presentation by Joakim Krook of Linkoping

University)

Waste type % by weight

Fine fraction 50 – 60

Combustibles 20 – 30

Inorganics ~ 10

Metals <5

A detailed study of waste composition at the Remo landfill in Belgium is provided in a presentation

titled ‘valorisation of materials within enhanced landfill mining: what is feasible ?’. This presentation

describes waste composition of various known ages and from varying depths in the landfill. The

overall composition described is reproduced in Table 1.3.


Table 1.3 Typical composition of waste excavated from the Remo landfill in Belgium (from a

presentation titled ‘valorisation of materials within enhanced landfill mining: what is feasible?’)

Waste type (Municipal Solid Waste- mostly

commercial and industrial MSW) % by weight

Stone 10

Wood 7

Metal 3

Plastic 17

Textile 7

Paper/ cardboard 8

< 10mm 44

Waste type (Industrial Waste) % by weight

Stone 10

Wood 7

Metal 3

Plastic 5

Textile 2

Paper/ cardboard 2

< 10mm 64

The data in Tables 1.2 and 1.3 broadly aligns with that in Table 1.1, as does data in further papers

reviewed on the composition of excavated landfilled wastes. Whilst the composition at the Remo

landfill in Belgium (Table 1.3) suggests waste richer in materials for recycling or energy recovery than

in Table 1.1, it should be noted that the Remo landfill in Belgium is anticipated to shortly commence a

LFMR operation undertaken primarily for material and energy recovery. The data in Table 1.3,

therefore, represents waste quality from a landfill specifically identified as appropriate for LFMR. It is

concluded that the waste in Table 1.1 represents ‘typical’ excavated waste quality, and that the

composition in Table 1.3 represents a particularly good quality for recovery of recyclable materials and

energy recovery.


1.3 Oil Shale Bings of West Lothian

Oil shale bings are heaps of waste comprising shale residues from historic extraction of oil from oil

shale deposits. Bings can be found across Scotland, although this study is limited to West Lothian’s

remaining 19 bings, which collectively occupy an area of 330 hectares.

The 19 remaining bings in West Lothian all closed for receipt of oil shale deposits between the 1920’s

and 1960’s. Since then, some have been restored, involving re-profiling, placement of soils and

planting, some have been left alone and some have been worked to remove material for use in

construction.

It is possible that the material in the bings is still of economic benefit. It is also a fact that bings are of

amenity value to local communities and visitors and some of them are of particular ecological value,

as is well documented in academic and planning authority literature. Section 3 of this study is

concerned with discussing these issues.


2 Landfill Mining and Reclamation Feasibility and Evaluation

2.1 Historic and current LFMR projects worldwide

2.1.1 History of LFMR

The first LFMR project took place in Israel in 1953. Since then, in excess of 60 projects are reported in

the literature. Sites and project drivers identified in the authors literature review are provided in

Appendix 4.

Whilst there is frequently more than one driver at any one site, a summary of the principal drivers are

detailed in Table 2.1 below. All projects are identified in the table, including where the project was to

investigate suitability for energy recovery where energy recovery did not occur, where a project was

undertaken as a pilot study or research project and where a project was considered but not

undertaken. Whilst other authors frequently note there have been in excess of 60 LFMR projects, the

authors of this report have only considered projects that have come to their attention, which are 57 in

number.

Table 2.1 Principal drivers for historic and current LFMR projects worldwide

Principal project

driver

UK (no.

projects)

Europe (excl.

UK) (no.

projects)

North

America (no.

projects)

Asia (no.

projects)

Total

projects

Not specified 12 4 2 18

Voidspace recovery 3 4 7

To allow site

redevelopment 3 2 1 6

To mitigate pollution 2 5 1 8

To improve landfill

engineering (e.g. meet

regulatory

requirements)

3 1 2 1 7

Material reclamation

for recycling or energy

production

3 2 6 11

Total projects

6

23 projects

across 8

countries

17 projects of

which 1 in

Canada and 16

in the USA

11 projects

across 7

countries

57


Given the amount of landfills in existence around the world, very few landfill mining projects have

taken place since the first recorded project in 1953. The documented projects undertaken are spread

around the world in North America, Europe and Asia. The USA is the individual country which has

undertaken the most LFMR projects.

It is evident that whilst material sorting and recovery, in particular soil, often features in a LFMR

project, it is seldom the main project driver. Where it has been the main driver, six of the projects

have been in Asia where two of the projects were solely undertaken to utilise soil as compost (one

was a pilot project), three were solely for energy recovery (two were research projects) and one was

for use of soil as fertiliser and for energy production. Of the two such projects in the USA, one was

undertaken to investigate material recovery and markets (Perdido Landfill in Florida) and the other

was to feed a nearby mass-burn plant for a defined period of time to meet capacity requirements. Of

the three such projects in Europe, two were for energy recovery and material recycling (but these

were just research projects) and the other is the Remo landfill project in Belgium which is yet to

commence but will be undertaken for the recovery of materials for both recycling and energy

recovery.

Many of the projects reviewed involved only basic separation of wastes, principally separation of the

soil fraction by screening.

2.1.2 Case studies

Four projects have been selected to provide insight into the different types of historic or on-going

LFMR projects.

Case Study 1- Packington Landfill, Birmingham, UK (Stuart Hayward-Higham, 2008)

Packington Landfill was the first of three significant landfill mining projects undertaken by Sita in the

UK, which when combined involved the movement of almost 1 million cubic metres of waste. These

projects were undertaken for the purpose of improvement of cell engineering, and therefore resource

recovery or reclamation of land were not the driving factors.

Packington landfill is located on the eastern edge of Birmingham, and is one of the largest land raise

landfills in the UK. When mined, the landfill was over 50 years old, and had been filled with waste of

varying form, composition and different filling geometries. The motivating factor behind the project

was the need to make repairs to the basal seal of one particular cell. This necessitated the movement

of 650,000m3 of waste, estimated to have been landfilled in the 1970’s.

Almost six months was spent on the investigation of filling history and to determine the boundaries of

adjacent cells. In order to do this, many sources of information were reviewed, including old

photographs, interviews with long serving staff, historic filling records and borehole data. This

investigative process revealed that a large amount of demolition waste, including concrete, would be

present in this cell. The method of excavation was then designed with this in mind. Sita identified that

bagged and loose asbestos was likely to be present. Special measures were used each time asbestos

was identified, which included dousing the material with water until it was collected and buried at an

active tipping face.

The design process specified that all excavation works would be undertaken in a continuous water

mist, to minimise the risk of dry materials becoming airborne. Close communication with site

neighbours and regulatory authorities was maintained prior to and during the project. The nearest

properties were less than 150m away and some properties were always within 400m of the mining

operation throughout its entire duration.


During the works, gas extraction was maintained wherever possible and the nature of the cell meant

that only minor works were required to control leachate.

The operations at the Packington landfill and the two other landfills, were not undertaken to recover

material or energy. However, Sita concluded that identifying the material present, and therefore its

value, would need to be far more involved for recovery operations compared to straight excavate and

relocate operations. It was noted that this would not be easy. Sita also noted that effective separation

of excavated wastes would be harder than many people realise, stating it is ‘the greatest challenge

yet to be solved’, and noted that they have considerable experience of operating separation facilities.

In summary, Sita commented ‘landfill mining, practical yes, technically possible, potentially

commercially viable, but far more complex than you may initially think’.

Case Study 2- Masalycke Landfill, Sweden (Reno Sam, 2009)

The Masalcyke landfill in Sweden was included as part of a landfill mining research project to

understand the stage of degradation of landfilled wastes with a view to considering their potential for

recycling and energy recovery. The municipal landfill, dating from the 1970’s, is also being considered

for expansion due to the need for more capacity in the locality.

The excavation was minimal in comparison to the size of the wider landfill. Three sizes of screen were

used (<18mm, 18-50mm and >50mm) separating out the different fractions of waste. Composition

was found to comprise around 29% paper, 19% wood and 17% miscellaneous (mainly comprising

organic and inorganic soils or unidentified items), others include stones, hazardous waste and other

recyclates.

Outputs of the landfill mining process included a soil fraction for soil improvement, a moistened

organic fraction that was placed back in the landfill for gas recovery, plastics were separated for

shredding and reprocessing into ‘Polyplanks’ (a mixture of plastic and wood) for construction purposes

and the remainder was placed back in the landfill. The degradation of materials in the central layers of

the waste appears to have been less than at the base and at the top and this was considered to be

related to moisture content.

Case Study 3- Halifax Landfill, Vermont, USA (Reno Sam, 2009)

The Halifax landfill in Vermont, USA, is a small rural landfill of less than 1 acre. The landfill needed to

be re-profiled due to steep slopes arising from tipping from above creating 1:1, poorly compacted,

waste slopes which prevented effective closure. Therefore, removing (mining) the waste was

considered necessary, in order to replace the waste at gradients of 1:3. During mining, 95,800 cubic

yards of materials were passed through a trommel screen and waste materials were placed back into

the landfill and compacted. The soils, separated by the trommel, were stockpiled and used in the

town as road base and fill, they were also mixed (1:3) with local biosolids to form ‘topsoil’ on

completion of capping at the site. It was later found during post-closure monitoring that tomato,

pepper and melon seeds had sprouted.

The Halifax landfill received wastes from the 1970’s to its closure in 1992 and, following mining, it was

capped in 1995. Wastes landfilled comprised municipal household waste. The nature of the landfill

filling process meant that considerable quantities of soil as daily cover were laid (in some cases 3-4ft

deep), in order to reduce the risk of punctures to vehicles placing wastes. Following excavation, the

soil:waste ratio, was found to be around 1:1. Grant funds were provided by Vermont State to fund

the work.


Case Study 4- Remo Landfill, Houthalen-Hechteren, Belgium (Steven Van Passel et al,

2010) (Waste Management World, 2011)

Advanced Plasma Power (APP) is in collaboration with a number of academic partners (KULeuven,

VITO and UHasselt) and with Group Machiels. This collaboration brings together Group Machiels’

concept of ‘enhanced landfill mining’ with APP’s Gasplasma technology under their ‘Closing-the-Circle’

project banner.

The project will mine a Belgian municipal (MSW) and industrial (IW) solid waste landfill, the Remo

Milieubeheer NV landfill, which received 16Mt of waste from the 1970’s onwards, roughly half of which

is household waste. The remainder of the waste is industrial waste such as shredded material from

the automotive industry, metallurgical slags, pyrite containing slags, dried sludge, etcetera. The area

of non-hazardous fill to be included in the project is circa 129 hectares. The landfill is engineered such

that it is compliant with Flemish legislation and the EU Landfill Directive and has leachate collection

and treatment and methane recovery.

The project is looking to capture and generate between 75MW to 100MW of electricity, enough to

power 100,000 homes, to supply the national electricity grid. The remaining product will be APP’s

trademark Plasmarok which is a vitrified mass of material.

The landfill is located in Flanders, a densely populated area. This site was chosen partly due to its

age as it is widely agreed that the nature of an increasingly ‘consumer’ society between 1950’s and

1980’s will yield the highest, and more economically viable, recyclate levels. It is anticipated that the

waste is comprised of around 45% recyclates. During on-site investigations into waste composition in

2009 specific areas of MSW and IW filling were investigated, the breakdown of materials was as

follows: stone (10%), wood (7%), metal (3%), plastic (17% MSW and 5% IW), textiles (7% MSW

and 2% IW), paper/cardboard (8% MSW and 2% IW), <10mm (44% MSW and 64% IW).

With consideration of socio-economic matters, the impact of the value of reclaimed land, greenhouse

gas savings and contribution to EU renewable energy objectives, the parties involved in this project

deemed it a viable project.

The LFMR operation has yet to begin. Public inquiries have taken place in 2012 and, through

discussion between Ricardo-AEA and APP, it is understood that regulatory considerations are currently

the main consideration delaying commencement of the project. Ricardo-AEA were informed that in

Belgium planning and permitting applications are not normally drafted in parallel as is common in the

UK.

In addition to stressing the importance of regulatory issues to a LFMR project, Ricardo-AEA were

informed by APP that the issues listed below are also highly pertinent to feasibility.

Understanding waste composition is crucial. Where this is not well understood, the project may be

too risky and costs cannot be scoped appropriately.

Presence of hazardous wastes can significantly complicate matters, increase costs and affect

viability.

Viability is subject to some form of government financial support, in particular for energy

production or credits for carbon emission avoidance, e.g. avoidance of fugitive emissions of landfill

gas to atmosphere.

Considerations such as real estate value and voidspace recovery can play a significant part in

economic viability.


2.1.3 Feasibility studies undertaken elsewhere

A number of authors of papers reviewed for this study have undertaken LFMR feasibility assessments.

Selected information from three of these papers are discussed below. Many of these findings are

commonly cited and discussed in LFMR literature.

A paper presented at the Thirteenth International Waste Management and Landfill Symposium in

Sardinia in 2011 considers the feasibility of sustainable material and energy recovery from landfills in

Europe (W.J. Van Vossen and O.J. Prent, 2011). Costs discussed in the paper refer to the Dutch

situation and the authors determined composition based on review of available data from 60 LFMR

projects (as discussed in Section 1.2.2) and considered a ‘standard landfill’ to be 500,000 tonnes and

5 hectares in area. The paper primarily focused on metal recovery. Some of conclusions of the authors

are listed below.

Separation techniques are available and proven and, therefore, landfill mining is technically

feasible.

Of the 60 LFM projects reviewed in literature, the authors note that recycling and recovery of

materials are not the most common goals of LFM projects. The most common drivers were noted

to be increasing landfill capacity and clearing the area for urban development for financial benefit.

The assessment considers processing which utilises handpicking (incompatibles), shredder, drum

sieve (soil), magnet (ferrous metals), drum separator (paper and plastic as the light fraction, C&D

waste, stones and glass as the heavy fraction and wood, organics and textiles as the medium

fraction), eddy current separator (non-ferrous metals) and air knife (plastics and wood)

applications.

The revenue from extracted metal is sufficient to offset mining costs by 8.2% where full separation

of the waste occurs and by 18% where only ferrous metal is separated from the waste excavated.

These percentage cost reductions are significant when it is considered that the assessment

considers only 2% metal content in the landfill.

After the revenue from metal recovery is considered, there remains a large deficit to be addressed

in order to make LFM profitable.

Re-using the freed landfill capacity as new landfill (e.g. voidspace recovery), reusing the landfill

area for urban development and selling the other recovered material streams are cited as ways of

making landfill mining more profitable. The authors note ‘acquiring these additional benefits

strongly depends upon specific local circumstances and conditions. In the optimal case, these

additional benefits might compensate the total costs and might generate a return on investment of

10 to 20%. From this point it cannot be excluded that a landfill mining project might become

financially profitable’.

The application of the soil fraction in close proximity to the mining project is cited as having a big

influence on the overall viability of a ‘material from landfill’ project.

Whilst separation techniques are available and proven for certain waste streams, as stated by the

authors of the Dutch study, Ricardo-AEA consider that they are not well proven in the field of LFMR.

Ricardo-AEA do however, agree that LFMR is technically feasible.

In 2009, Reno Sam published a report titled Landfill Mining – Process, Feasibility, Economy, Benefits

and Limitations. Reno Sam is a Danish association of municipal waste management companies. The

report compiles experiences from a range of landfill mining projects throughout the world, and uses

them to examine issues relating to the overall feasibility of landfill mining in Denmark. A summary of

the key observations of this study are:


Factors impacting on the economic feasibility of reclamation differ for each site, and the reason for

which each is mined.

In some specific circumstances, the recovery of ferrous metals, aluminium, plastic and glass and

fines can make a project economically viable, if these materials are present in significant quantities

for recovery.

In some locations, the lack of waste-to-energy facilities limits the market for combustible materials,

and therefore impacts on the potential value of materials recovered.

Site specific conditions which will help decide whether landfill mining is feasible at a specific site

include:

Waste composition.

Historic operating conditions.

Extent of waste degradation.

Markets and prices for recovered materials.

The report suggests that a landfill should be at least 15 years old before a successful landfill

mining project can be undertaken.

In one project, costs for recovery were low as the distances involved in transporting reclaimed

waste and ash were low, and the management authority used their own vehicles.

The costs of material recovery can be offset by reductions in closure costs and the reclamation of

land for other uses, and so facility operators need to take this into account when determining

feasibility.

The economic feasibility of landfill mining can depend on depth of waste and the soil to waste

ratio, i.e. the deeper the waste is buried, the more expensive it is to mine.

The report concluded that undertaking landfill mining for purely economic reasons is not viable.

A paper titled ‘Enhanced Landfill Mining: Material recovery, energy utilisation and economics in the EU

(Directive) perspective, (Hogland, Hogland and Marques, 2011) also examined the issues of technical,

environmental and economic feasibility and concluded that:

From a material recovery point of view, landfill mining of MSW landfills should focus on landfills

which were established between 1960 and 1995, as after this date most EU countries had

introduced recycling programs.

Landfills which accepted industrial wastes may contain more valuable material, i.e. car

fragmentation material and electronic wastes.

As some incinerators in Europe are now suffering from overcapacity, they are a more likely output

for waste recovered from landfill mining.

Economic feasibility should include the reduction or elimination of capping, long-term monitoring

and aftercare, maintenance and potential remediation costs, as well as the future value of

reclaimed land.

Economic feasibility is directly related to capital costs (site preparation, purchase or rental of

equipment) and operational costs (labour, material handling, regulatory compliance).

The EU Waste Directive will continue to drive waste minimisation, pre-treatment and recycling, and

therefore will make newer and future landfills less feasible for mining.

Local conditions are fundamental when assessing economic feasibility.

2.2 Implications of worldwide experience to landfill mining in Scotland

The findings and observations reported in the literature for historic and current LFMR around the

world are very pertinent to assessing the feasibility and viability of LFMR in Scotland. Many of the

findings will apply in Scotland, although consideration needs to be given to the specific issues that

apply in Scotland and this is done in Section 2.3.


A key LFMR project that is of particular interest is the APP/Machiels project at the Remo landfill in

Belgium. Although this project is yet to commence, it is the first full-scale project of its kind and it is

being undertaken primarily for resource/energy recovery purposes. Other historic and on-going

projects are either limited to pilot or research projects or have been undertaken primarily as a result

of other drivers. This is a modern-day project that is likely to inform future LFMR projects worldwide.

As historic projects undertaken around the world have generally not focused on resource recovery as

the main driver, the types of separation technologies that are likely to be considered are little proven

for separating excavated landfilled waste. Excavation, shredding and screening has been undertaken

extensively, but further separation technologies have not been widely utilised.

The authors experience of separation technologies treating fresh municipal solid waste (MSW) is such

that it is considered unlikley that sending excavated landfilled waste, or fractions of waste, to an

existing materials recovery facility (MRF) is likely to be feasible. Modern facilities such as MRFs and

Mechanical Biological Treatment (MBT) facilities are designed to treat a certain waste stream(s) and

waste stream composition ‘envelope’. Variations in waste quality can give rise to processing problems

such as blockages, high rate of equipment wear or damage and inneficient separation. Changes in

waste quality can result in the need to amend the manner of operation and to make adjustments to

equipment.

The condition of the waste on arrival, as well as the composition, can influence separation efficiency.

For example, loose co-mingled dry recyclables cannot be separated so well if they have been placed in

a vehicle that compacts waste as opposed to one that does not. The degree of compaction, moisture

content and intertwining of wastes all effect separation efficiency. Landfilled wastes in particular are

likely to be mixed, intertwined and compacted in a manner that will not lend itself to ease of

separation in an existing facility. Landfilled waste is likely to be highly variable in quality and nature at

any one given landfill. Variation is likely to exist as a function of where different waste streams were

deposited, variation subject to age of waste, depth of waste, whether or not the waste is saturated,

moist or dry and the degree of degradation that has taken place. No two landfills will be the same and

sorting, shredding and separation technologies will most likely have to be designed and specified for

the particular landfill concerned and the degree of anticipated variation in quality and nature of the

waste. Where separation of waste into a high number of products is required, it should be noted that

separation efficiency and product quality are unlikley to be high in comparison to treatment processes

for non-landfilled wastes.

The general view obtained from the literature review is that, unless other drivers are also considered,

LFMR for the purpose of resource recovery is not currently economically viable. Certainly, the

impression is that making such a project economically viable would be a challenge requiring an

optimum set of physical, political and economic conditions, careful detailed desk study research and

careful consideration of a complex mix of issues. However, not many of the projects to date have set-

out to maximise resource recovery to the full extent and the technologies applied to date have, in the

main, been limited. The Remo landfill project is evidence that it may, or may soon, be possible to

undertake an economically viable LFMR project.

It is important to note that many of the projects undertaken around the world to date have occurred

in diverse locations and over a period of 60 years. The feasibility of a LFMR project in Scotland should

be viewed in the current climate of regulation and environmental drivers such as reduction of

greenhouse gas emissions and increasing resource scarcity.

A number of the projects historically undertaken around the world have utilised soil from LFMR as a

fertiliser or growing medium. In addition, it has commonly been used as landfill daily cover. Use as

daily cover is likely to be acceptable in Scotland, although determination of this would depend on

discussion with SEPA on an individual site basis.


Due to quality considerations, use of soil for a fertiliser or growing medium may not be acceptable to

regulators. Given that soil can typically constitute around 50% of waste excavated from a typical

landfill, soil end use is likely to be very pertinent to the viability of a LFMR scheme in Scotland.

From Ricardo-AEA’s review of LFMR literature, listed below are commonly cited issues, associated with

feasibility, which should be borne in mind when considering feasibility and viability of a LFMR project

in Scotland.

It is first necessary to fully understand the nature of the waste present in order to establish the

business case for LFMR and to inform the design of the LFMR plant and equipment.

The degree of soil present within the landfill and what can be done with the soil following

separation is a key consideration.

Economic considerations, and technical issues, are influenced by the area of the landfill, depth of

the landfill and height of leachate or groundwater within the waste mass.

The presence of hazardous wastes can notably influence the operational procedures and add

additional costs to a project. In all cases, it is necessary to ensure measures are in place to

identify, remove and appropriately manage inappropriate or hazardous waste.

Extending the life of a landfill by recovery of voidspace, or by placement of an engineered liner,

increasing the real estate value of the land or the remediation or prevention of contamination are

all factors that have driven historic and current projects. Such factors, coupled with resource and

energy recovery, will increase the viability of the LFMR project in Scotland.

Local markets and treatment facilities or energy recovery facilities for recovered materials will

influence the viability of a LFMR project in Scotland.

2.3 Evaluation of issues (Scotland)

2.3.1 A ‘typical’ Scottish landfill

In scoping the feasibility and viability of LFMR specific to Scotland, it is necessary to first establish a

set of assumptions on which the assessment is to be based. These assumptions have been drawn

from the discussion of Scotland’s landfills and excavated waste composition in Section 1.2.

Scotland’s landfills vary considerably in age, size, depth and waste composition. However, the authors,

with consideration to available data, consider that the information provided in Table 2.2 below

provides the best description of what could be considered a ‘typical’ licenced/permitted non-hazardous

landfill in Scotland. It should be noted that only 48 of the 218 licenced/permitted non-hazardous

landfills are operational.


Table 2.2 Attributes of a ‘typical’ non-hazardous Scottish landfill

Attribute (single ‘typical’

landfill) Value Comment

Overall mass of waste 1.3 million tonnes Ignoring Scotland’s 2 largest

non-hazardous landfills, the

median total capacity of

operational non-hazardous sites

is 1.3 million tonnes.

The total capacity of closed but

still licenced sites is not readily

available.

Depth of waste 15m This is an arbitrary depth.

Depth will vary greatly between

landfills, and in many cases

across a single landfill.

Landfill area 10 hectares This is derived from the total

assumed tonnage, the assumed

depth and the assumption that

the waste density is 0.9 t/m3.

Waste composition Non-hazardous and a mix of

household, commercial and

industrial waste.

‘Typical composition’ as

presented in Table 1.1.

‘Good composition’ as presented

in Table 1.3.

Based on literature review, as

discussed in Section 1.2.2.

No Scotland specific data exists

for excavated waste quality.

The majority of landfills

(operational or closed) receive/

received household, commercial

and industrial waste.

Presence of other waste

management facilities at the

landfill

Assume none More than half (59%) of

operational non-hazardous

landfills are landfill only sites

The majority (91%) of closed

non-hazardous landfills that are

still licenced are landfill only

sites.

Whilst the ‘typical’ licenced/permitted non-hazardous landfill has been established, as described in

Table 2.2, it is necessary to consider other variables such as those listed in Table 2.3 below.


Table 2.3 Further variables for a ‘typical’ non-hazardous Scottish landfill

Landfill type Considerations

Non-hazardous

landfill

Operational With and without other waste facilities at the same

location

With and without an asbestos cell/s

With and without cells of low landfill gas production.

With ‘typical’ capacity and with range of capacities.

Closed With and without other waste facilities at the same

location

With and without an asbestos cell/s

With and without cells of low landfill gas production.

With ‘typical’ capacity and with range of capacities.

With and without known presence of hazardous waste.

With and without Landfill Directive compliant base and

sides.

To inform the discussion of issues, in particular technical, economic and environmental issues, it is

necessary to consider how non-hazardous landfills containing biodegradable waste behave over time.

When deposited in a landfill, waste exists in an aerobic state for a brief period of time, typically days

or weeks, before anaerobic processes take hold. During this brief period, aerobic degredation primarily

gives rise to carbon dioxide gas. With time, the oxygen present within the waste is consumed and

new oxygen is prevented from entering by subsequent waste and daily cover placement. Under these

anaerobic conditions, microbial breakdown of the waste primarily generates methane, typically around

60% volume/volume (v/v). As the waste landfilled increases in quantity and age, the predominant gas

produced is methane.

When the landfill is full, it is normally capped and restoration soils are typically placed on top of the

capping material. The capping serves numerous purposes including minimisation of leachate

generation, minimisation of air entry and maximisation of gas collection efficiency. Utilisation of

discreet landfill cells allows can allow easier progressive capping and restoration and can assist in

controlling leachate levels within the waste, as well as allowing progressive gas collection and ease of

controlling gas collection. It is preferable to maintain leachate levels around 1m height and a high

level can slow down the degredation of waste within the leachate. As waste filling progresses, bulk

gas generation normally increases fast, typically reaching a peak around, or shortly after, the end of

the filling operation. The bulk gas generation then tails-off exponentially. Where gas is utilised in an

engine or turbine to generate electricity, the time will come when there is insufficient gas for this. At

this point, gas generated is typically collected and flared.


The time will then come when there is insufficient gas to collect and flare. At this point in time, it is

inevitable that gas will be lost to the environment. Pertinently to environmental considerations, this

low level generation of gas can occur over a very long period of time, owing to the exponential nature

of the fall in generation levels. Eventually, when it is proven that the waste has fully stabilised and the

regulator is satisfied that the landfill no longer poses a risk, the operator will seek to surrender the

permit for the site. This is pertinent to the economic discussion as this will be long after the end of

income from landfilling and electricity generation, after which time the operator will still be paying to

maintain and monitor the site, as well as costs involved in reporting to the regulator and maintaining

the site’s permit.

It is important to note that many closed landfills will not meet modern landfill engineering

requirements which afford a high degree of containment, control and minimisation of leachate

generation. In addition, not all landfills contain discreet engineered cells and this applies to landfills of

all sizes. It is also important to note that a range of factors, such as waste type, density, pH,

temperature and moisture content can influence the rate of degredation. As such, the timeline for the

above sequence of events will vary site by site. The timeline is pertinent to when it would be

appropriate to commence a LFMR operation and in assessing any avoided costs and avoided

environmental impacts.

Table 2.4 below identifies an assumed timeline that is considered appropriate to apply to the ‘typical’

non-hazardous Scottish landfill described in Table 2.2.

Table 2.4 Proposed timeline of a ‘typical’ non-hazardous Scottish landfill

Event Date of event or duration Comment

Ending of filling and provision of

capping

Will vary from site to site Since decisions will be made on

the age of the landfill, it is

important to establish when this

date was.

Peak gas generation Typically around or shortly

following end of waste receipt

and capping

Based on author experience of

landfill gas modelling

Utilisation of gas in an engine or

turbine

18 years Based on author experience of

landfill gas modelling, this is

typically 15 to 20 years. An

example model in the

Environment Agency’s GasSim

software describes a landfill of

similar nature (1.9M tonnes, 8.3

hectares and containing non-

hazardous domestic and

commercial wastes) to the

‘typical’ Scottish landfill

discussed above. The model

shows utilisation to take place

over an 18 year period.


Event Date of event or duration Comment

Period of insufficent gas for

utilisation, but sufficient gas for

flaring

6 years Based on the example GasSim

model discussed above.

Period in which gas is generated

at low level which cannot be

effectively collected.

45+ years This is somewhat arbitrary and

will vary significantly from site to

site. This is based upon author

experience of landfill gas

modelling and review of

literature. SEPA guidance on

‘financial provision’ (SEPA, 2005)

describes ‘at least 60 years’ for

an aftercare period for

biodegradable non-hazardous

landfills and notes that the actual

duration will be very site specific.

This aftercare period reflects the

time from the ending of waste

deposit to permit surrender.

Due to risks associated with excavating into recently deposited wastes that are still generating high

volumes of gas and high strength leachate, LFMR operations are normally undertaken on wastes that

have achieved a certain level of stabilisation. Although the age will be variable, this scoping study

assumes it is undertaken 25 years following ceasation of filling. In order to undertake a LFMR

operation earlier than this, it is possible to increase the rate of degredation and stabilisation through

creation of an aerobic landfill. In doing this, methane production is greatly reduced, carbon dioxide

production increases and the rate of stabilisation increases which can significantly bring forward the

time at which LFMR can take place. This will alter the economic and environmental aspects of the

project. However, the material available for recovery at the end, the key focus of this high level study,

will remain broadly the same. Furthermore, the waste of most interest for LFMR projects undertaken

for material reclamation is considered to be that deposited in landfills between approximately 1965

and 1995. For these reasons, whilst the aerobic landfill approach may be of interest for certain

scenarios, this scoping study has been undertaken with consideration of the ‘typical’ timeline provided

in Table 2.4.

2.3.2 Overview of economic issues

As highlighted in Table 2.1 and in the Packington Landfill case study in Section 2.1.2, landfill mining in

the UK has been restricted to projects where waste has needed to be moved to undertake repairs to

the landfill liner, or to relocate the waste to make way for a road or other new infrastructure. The

costs of these projects were perhaps seen as inevitable or unavoidable. Where landfill mining is being

considered for the purposes of resource recovery and/or reclaiming land or void space, the economic

viability becomes fundamental to deciding if a project should be undertaken.

The economic factors associated with landfill mining are complex and numerous. Some costs may be

straightforward to estimate, whilst other costs will be more difficult to quantify. Other than the value

from future land sales or new void space, revenues from recyclables are acknowledged to be the

other main source of income in landfill mining projects. Landfills may be potential future ‘mines’ of

recyclable materials, but the on-going uncertainty surrounding markets and prices for recyclables

makes estimating the potential revenues difficult. Some studies have indicated that landfill mining for


the sole purpose of recycling of materials is not cost effective (Morris, 1994) but that the greatest

potential economic benefits are associated with the land value of reclaimed sites, and avoided or

reduced costs of landfill closure.

Attempts have previously been made to develop generic Cost Benefit Analysis (CBA) models for

determining the economic feasibility of landfill mining. However, the variation in parameters such as

waste quantity, waste type, energy content, investment costs, operation costs, and revenues, mean

that this is still not possible other than on a site-by-site basis.

One such theoretical CBA was applied to the Enhanced Landfill Mining (ELFM) projects in the Flanders

region of the Netherlands (Van Passel et al, 2010) which established that recovering energy from

waste was the most important benefit, see Table 2.5 below. The CBA included the costs of land

currently used for landfills, and a monetary value was assigned to greenhouse gas savings based on

the EU Emission Trading Scheme. The research concluded that ELFM projects would have a positive

benefits, but that there were complex trade-off between economic, social and environmental issues.

Table 2.5 Social Cost Benefit Analysis for ELFM in the Flanders region (Van Passel et al, 2010)

Cost Benefit Analysis for ELFM in Flanders

Site surface (m2) 20,000,000

Costs (EUR)

Total 12,779,680,000

Benefits (EUR)

Total waste to materials 1,534,382,080

Total waste to energy 9,937,782,556

Landfill reclamation 1,368,000,000

Reduced carbon footprint 256,650,240

TOTAL 317,134,876

Table 2.6 below summarises the main costs and sources of income/revenue of an LFMR project.


Table 2.6 Costs and sources of income/revenue of an LFMR project.

Costs Benefits

Project Planning Revenues

Investigative studies

Obtaining permits and planning consent

Consultancy and design costs

Sale of recyclable materials

Reclaimed soils (either reused on-site or sold as

construction fill materials)

Energy recovery and incentives

Capital Costs Avoided costs

Site preparation

Equipment and plant

Post closure care and monitoring

Purchase or development of new landfill

Liability for future remediation

Operational Costs Other benefits

Labour

Fuel/ energy

Maintenance of equipment

Rental of equipment

Transport and haulage costs

Landfilling of residual materials

Administration and regulatory compliance

Staff training

Gate fees for combustible materials at EfW

facilities

Potential value of reclaimed land

Potential value of recovered void space

2.3.3 Economic issues specific to Scotland

2.3.3.1 Expected material recovery rates for Scottish Landfills

As outlined in Section 1.2.2, it is not possible to determine an accurate waste composition and,

therefore, expected material recovery rate without undertaking detailed studies at a specific landfill. A

typical compostion of a landfill in Scotland, with the absence of specific data, is considered to be that

given in Table 1.1.


Prior to the introduction of recycling in the 1990’s, older wastes going to landfill contained more

metals, glass and organic waste than wastes from the 1990s onwards. Prior to the increasing

consumer society of the 1960s onwards, landfilled wastes are likely to contain less recoverable

materials. It is, therefore, considered that wastes from the mid 1960s to the mid 1990s are likely to

contain the highest amount of materials of interest to a LFMR project focusing on resource recovery.

Savage et al (1993) estimates the proportion of various materials which it is possible to recover are as

high as 80-95% for metals and 70-90% for plastics.

Based on review of available information and mechanical processing efficiencies, Kit strange of the

World Resource Foundation (WRF), noted expected recovery rates of:

85% to 95% for soil.

70% to 90% for ferrous metals.

50% to 75% for plastic.

He also notes expected material purity as detailed below (the higher end of each range noted as

reflecting relatively complex process designs):

90% to 95% for soil.

80% to 95% for ferrous metals.

50% to 75% for plastic.

For simplicity, given the approximate assumption of ‘typical’ waste given in Table 1.1 and that a better

quality could be encounterred in a carefully selected landfill (Table 1.3), the high level economic

assessment of a ‘typical’ landfill (Section 2.3.4) has considered that all recoverable waste is recovered.

2.3.3.2 Markets, off-takers and revenues in Scotland

Metals

The primary materials recovered for recycling are anticipated to be both ferrous and non-ferrous

metals. Metals are likely to be one of the simplest materials to be recovered, and also have the

highest value. The metal recycling market in the UK is such that the lack of proximity to an end user

of recycled metals is not a significant barrier to its recycling. There are numerous waste management

and recycling companies across Scotland with the capacity to collect, bulk and transfer metals on to

end users in the UK, or indeed for export. It is anticipated that metals would be sold at the current

market value, which is subject to the global commodities market, with little influence from local

factors.

Plastics

Operators of MSW (non-landfilled) mechanical separation plants in the UK are currently, in general,

sending plastic for use as an RDF or SRF. Some operators are paying for their separated plastic to be

landfilled. Plastic separated in a LFMR is likely to be of poorer quality than plastic from non-landfilled

MSW. Even where attempts are made to separate film from hard plastic, to separate hard plastics by

optical sorting, or to clean the plastic, quality is still likely to be comparatively poor and the processing

cost high. The opportunities for finding a buyer of plastic segregated from excavated landfilled, with

the intention of using the plastic in manufacturing, are considered to be low.


Inert, Construction and Demolition (C&D waste), glass and soils

There are numerous materials recycling facilities and waste transfer stations that accept C&D and

other inert waste for recycling across Scotland, where they are recycled for reuse as aggregates, fill

materials and soils. The market for these materials is robust. However the quality of these materials

from a landfill is likely to be poor when compared to C&D waste being processed directly from the site

at which it arises. Materials are likely to be contaminated with soils, leachate and other organic

materials, resulting in increased difficulties in obtaining quality recyclable materials. Where the landfill

is to be subject to future landfilling, soil can be used for future daily cover and crushed C&D waste for

the construction of site roads. Soils recovered from landfill will be unlikely to meet quality criteria for

subsequent reuse offsite.

It is unlikely that glass will be able to be separated from other inert materials with a high degree of

purity and will have little value and so will be more likely to remain within the inert fraction.

Residual/Fuel Fraction

It is highly unlikely that the residual material from landfill mining will meet the requirements specified

for use as a Solid Recovered Fuel (SRF) for use in a cement kiln, therefore, this is not deemed to be a

viable market in Scotland at present.

There is potential for this material to be combusted in a conventional mass burn incinerator, with little

further processing. However, the current scarcity of Energy from Waste (EfW) facilities in Scotland

greatly impacts on the Scottish market for energy recovery from the residual waste fraction. There are

several EfW and Advanced Thermal Treatment (ATT) plants at various stages of development in

Scotland which may offer potential future markets for a residual fuel fraction from a LFMR project.

Details of these facilities are summarised in Table 2.7 below.

Table 2.7 Planned and proposed energy recovery facilities in Scotland (Ricardo-AEA database-

‘FALCON’)

Operator Technology Plant Status Location MW Annual

Throughput

Energos ATT -

Gasification

Planning

granted

North Ayrshire 6.0 80,000

Energos ATT -

Gasification

Proposed Renfrewshire 9.0 120,000

Scotgen ATT -

Gasification

Planning

Granted

South

Lanarkshire

10.0 160,000

Shore Energy ATT - Pyrolysis Planning

Granted

North

Lanarkshire

13.7 160,000

Covanta Combustion Planning

Granted

North

Lanarkshire

24.0 350,000

Viridor Combustion Proposed Glasgow CIty unknown 200,000


Operator Technology Plant Status Location MW Annual

Throughput

J Gordon

Williamson Ltd

Combustion Planning

Granted

Moray 4.0 30,000

Combined

Power & Heat

Highlands Ltd

Combustion Planning

Granted

Highland unknown 100,000

Sita Combustion Proposed Aberdeenshire unknown 100,000

If all of these plants progress to construction and operation, capacity to process residual fuel fractions

from LFMR would increase significantly and it is likely that some of these plants would be actively

trying to source additional feedstocks in addition to any local authority or other contracts they had

secured.

Another potential market would be for export to Europe for use as a Refuse Derived Fuel (RDF). There

is currently high demand for RDF in Europe, and exports from the UK are increasing. However, even

though quality requirements for RDF are not as stringent as for SRF, it is still unlikely that the residual

material from landfill mining would meet these requirements without an element of further

processing. Key quality criteria are moisture content, particle size and chlorine levels. A means of

overcoming this barrier would be to process the waste further in a Mechanical Biological Treatment

(MBT plant). Again, there are currently limited examples of such facilities in Scotland, and those that

do exist would tend to be tailored to processing a specific waste stream such as Municipal Solid Waste

(MSW) or mixed Commercial and Industrial (C&I) waste, and may not be configured to effectively

process the residual waste from landfill mining.

Energy Revenues and Incentives

The Renewables Obligation (RO), introduced in 2002, is a Government fiscal support mechanism for

supporting generation of renewable electricity. Under the RO, generators of electricity from renewable

sources can receive Renewable Obligation Certificates (ROCs) for each unit of electricity generated,

whether used on site or exported to the grid. However, to qualify for ROCs, the generator must be

connected to the grid via an import / export meter.

The rate at which ROCs are earned is dependent on the renewable electricity technology utilised.

ROCs will only be awarded for electricity generated from the biomass fraction (deemed or proven) of

the waste derived feedstock. EfW with power generation only, e.g. not combined heat and power

(CHP), is not eligible under the RO and consequently will not receive ROCs. However, both standard

and advanced gasification and pyrolysis technologies are eligible. The recent banding review

consultation by DECC has confirmed that advanced gasification and pyrolysis will receive 2 ROCs per

MWh in 2013/14, with standard gasification and pyrolysis also receiving 2 ROCS per MWh from

2013/14.

2.3.3.3 Do nothing scenario

In order to compare the potential savings and income of a landfill mining project, the costs of a ‘do

nothing’ scenario must be taken into account. If LFMR does take place, these become ‘avoided costs’.


SEPA has produced a technical guidance note which estimates the amount of financial provision that

needs to be made throughout the full life cycle of a landfill, and this document informed some of the

costs used in this high level assessment, in addition to author judgement.

The ‘do nothing’ costs are considered to apply for a period of 35 years from the end of when the

LFMR operation would have ceased had it have taken place. To further explain this, no costs are

avoided in the first 25 years folowing closure, and costs are not avoided during the subsequent 10

years of the mining activity. Avoided costs (or ‘do nothing’ costs), therefore, only arise after the first

35 years. Given an assumed 70 year full time period, that leaves 35 years of ‘do nothing’ or ‘avoided

costs’. Informed by the timescales in Table 2.4, this is based on the assumptions listed below.

Overall period of 70 years from end of waste receipt to permit surrender.

LFMR commences 25 years after end of waste receipt.

Mining operation for 1.3m tonnes (the ‘typical’ Scottish landfill, which is considered to be 10 ha and

15m deep) takes 10 years. It is assumed that the time limiting factor will be the advanced

mechanical separation processing following soil separation. Assuming 50% soil, an advanced

separation throughput of 25 t/hr and 2,700 hours of operation per year, gives a duration of 10

years. Available LFMR literature suggests excavation, shredding and trommeling can be undertaken

at notably higher throughputs. The advanced separation process throughput will be very much

subject to design, and advanced separation is little proven for landfilled wastes. The authors

consider that 25 t/hr is a realistic assumption.

Indicative costs of likely activities in the 35 year period are provided in Table 2.8 below.

Table 2.8 ‘Do nothing’ costs, e.g. costs that could be avoided through LFMR.

Activity/Item

Cost over 35

years (at 2012

rates)

Assumptions

Monitoring staff and reporting

£105k Based on 2 monitoring rounds per year and 3 days per round,

at a labour cost of £500 per day.

Laboratory costs for groundwater and leachate analysis

£150k Assume the site has 25 perimeter boreholes, 10 in waste

boreholes and 4 surface water monitoring points. Assume that

half of all boreholes and all surface water locations are

subjected to sampling and laboratory analysis twice per year.

Assume £100 lab costs per sample.

Treatment of differential settlement

£26k Assume £149.90/ha/yr (SEPA paper value adjusted for

inflation) and assume it applies for half of the period.

Annual permit charge

£87k Will be risk based and reduced in the aftercare period. This

value reflects the SEPA paper value adjusted for inflation.

Total cost (35

years)

£369k This total cost assumes leachate management is no longer

undertaken. This may not be the case, but any treatment is

likely to be notably less involved than within the first 35 years

after filling. It is also assumed that no gas management is

undertaken this long after waste receipt ceased.


2.3.3.4 Landfill gas

Utilisation of landfill gas in an engine or turbine to generate electricity, possibly with heat recovery, is

a source of revenue for a landfill operator. However, LFMR activities normally take place after the

waste has stabilised and, therefore, this revenue stream will no longer be present.

As discussed in Section 2.3.1, where landfill gas is being generated, the time will come when

generation levels are so low that it is not possible to collect and utilise it for energy or heat

generation. Gas is normally collected and flared when this occurs, which both manages the gas in a

controlled and safe manner and combustion emissions are of less global warming potential than the

raw landfill gas. However, levels of gas generation will continue to drop until collection and flaring is

not possible and then relatively low levels of landfill gas will be lost to atmosphere for a long period of

time, typically decades. This is an environmental impact and its avoidance could potentially represent

a signficant reduction in Scotland’s emissions of greenhouse gases. Landfill mining has the potential to

mitigate against this fugitive emission of landfill gas. In separating organic combustible material for

inclusion in an RDF for energy generation, the material is removed from the landill and it would,

otherwise, have degraded in the landfill giving rise to fugitive emission of landfill gas. In addition, it is

possible to screen the soil fraction recovered to remove the organic fraction. This concentrated

organic fraction can then be re-landfilled in a cell with gas collection for utilisation, or it could

potentially be sent to an anaerobic digestion facility for energy recovery. The latter option would,

however, give rise to payment of a gate-fee.




LFMR project economics.

The economic assessment presented in this study has not considered incentives/credits for avoidance

of fugitive emissions of landfill gas. It is, however, recommended that consideration is given to this

matter, in particular in relation to any possible future detailed site specific feasibility assessment, as

well as at a national policy level. In particular, consideration should be given to whether a LFMR

project in Scotland could qualify for Emission Reduction Units (ERUs) under the Joint Implementation

(JI) mechanism.

2.3.3.5 Capex and Opex

The capital expenditure (Capex) and operational expenditure (Opex) will vary significantly between

projects, and overall expenditure will be subject to a lot of variables. Depth of landfill, waste

composition, presence of hazardous waste, leachate level and waste moisture content, environmental

mitigation measures, level of reprocessing undertaken and choice of technology are some of the key

factors influencing Capex and Opex.

A review of international LFMR projects has revealed a wide range of capital and operational costs. In

some cases, capital costs were low as equipment used to process mined waste was leased or hired.

On larger projects such as the planned Remo landfill LFMR project in Belgium, which includes on-site

energy recovery, capital costs will be a significant proportion of total project costs.

Many costs discussed in literature reflect costs of operations limited to excavation, shredding and

screening, typically using leased mobile equipment. Many of the projects have also been relatively

short duration involving mining of relatively low quantities of waste.

Capex costs per tonne for USA landfill mining projects have been reported as ranging between $10 to

$30 (£6.20 to £18.60) and Opex costs per tonne at $30 to $90 (£18.60 to £55.80), giving a total cost

in the region of $40 to $120 per tonne, or £24.80 to £74.40 (Hogland 2011). These costs appear to


have included metal separation. Many USA LFMR projects have not, and do not, involve detailed waste

separation, noting the primary driver is seldom resource recovery.

The most recent cost estimates for processing mined landfill wastes are from a Royal Haskoning paper

presented at the Thirteenth International Waste Management and Landfill Symposium in Sardinia in

2011 (W.J. Van Vossen and O.J. Prent, 2011). The paper presents costs in Euros, based on Dutch

costs. These costs have been converted to pounds sterling and are presented in Table 2.9 below. The

paper is not explicit in noting whether these costs include Capex. However, the paper provides

‘construction’ costs eleswhere and the magnitude of the costs in Table 2.9 are such that the costs are

considered to refer to Opex. It should be noted that the paper is a feasibility paper and the costs are

not derived from an actual LFMR project.

Table 2.9 Estimated costs per step of processing mined landfilled waste (costs transferred to pounds

sterling, at €1=£0.80, based on euro costs provided in W.J. Van Vossen and O.J. Prent, 2011)

Separation Step Separated waste

streams

Costs per step

(£/tonne)

Cumulative costs

(£/tonne)

Excavation - £4.00 £4.00

Handpicking Non processables £0.80 £4.80

Shredder - £8.00 £12.80

Drum Sieve Soil £2.40 £15.20

Magnet Ferrous metals £2.40 £17.60

Drum Separator Paper & plastic (light

fraction output)

C&D, stones & glass

(heavy fraction output)

Wood, organic and

textile (medium fraction

output)

£5.60 £23.20

Eddy Current Non ferrous metals £4.80 £28.00

Air Knife Plastics & wood £12.00 £40.00

Cumulative costs up to and including the drum sieve (which is considered to be a trommel as the

authors are Dutch and ‘trommel’ is Dutch for ‘drum’ and ‘sieve’ is assumed to refer to ‘screen’) are

£15.20. If metal separation is added to this, the total is £22.40. This is at the lower end of the range

of Opex costs quoted for USA LFMR projects.

It is considered that Opex costs for a LFMR project in Scotland are likely to be broadly similar to costs

discussed in literature for US and european LFMR projects.


A paper presented at the Global Landfill Mining Conference in the UK in 2010 (Peter Jones, 2010)

provides estimated capital costs for investment in waste technology as detailed below.

Mechanical separation: £10m for a 100,000 tonne/annum facility.

Small scale advanced thermal treatment: £25m for a 50-60,000 tonne/annum facility.

Small scale gasifier/syn gas: £40m for a 60-80,000 tonne/annum facility.

Medium scale EfW: £60m for a 120,000 tonne/annum facility.

The paper estimates that LFMR processing costs could be around £25 per tonne, which is broadly in

line with the values discussed in Table 2.9.

With consideration to the range of costs discussed above, in addition to Ricardo-AEA judgement, the

economic analysis of a LFMR project undertaken on a ‘typical’ Scottish landfill has considered the

range of costs detailed below:

Opex for excavation and separation: £25 to £50 per tonne.

Capex for excavation and separation: £5m to £10m.

Opex for a gasifier with syn gas utilisation: £21 to £35 per tonne.

Capex for a gasifier with syn gas utilisation: £10m to £15m.

2.3.4 Economic analysis of a hypothetical Scottish LFMR project

Due to the complexities of the economics of landfill mining, it is not possible to present a ‘one size fits

all’ economic analysis. Specific site issues will be fundamental in determining economic viability in

each case. However, making some high level assumptions about a hypothetical ‘typical’ landfill in the

central area of Scotland, an indicative economic analysis has been undertaken. This is based on the

assumed ‘typical’ landfill described Section 2.3.1 and separation equipment described in a recent

paper on LFMR (W.J. Van Vossen and O.J. Prent, 2011). The simple assessment has been undertaken

to allow comparative analysis of a range of possible LFMR projects applied to the hypothetical, typical,

Scottish landfill. The assessment is based on 2012 costs and revenues and takes no account of future

inflation or other potential changes in costs or revenues.

The assessment is based on the assumptions listed below.

Landfill is to be mined, 25 years after closure, over a period of 10 years.

1.3 million Tonnes to be excavated, which would be the entire landfill contents.

15 metre deep cells.

10 hectare landfill area.

Separation is 100% efficient (for simplicity).

Soil is retained on site, either as daily cover for subsequent landfill, or as backfill and landscaping.

Use of residual waste (variables):

RDF is exported off site for energy recovery, incurring a gate fee.

RDF is used onsite at a purpose built facility, with income from energy sales and ROCs.

Recyclables (metals only) are sold at market value.

Land use after mining (variables):

Site is sold for development on completion LFMR project

Site operates as a landfill with new void space

Figure 2.1 outlines the processes and destinations for materials recovered a part of the economic

model developed.


Four different options have been modelled:

Option 1a – RDF exported for use off site, landfill void space free for reuse.

Option 1b – RDF exported for use off site, landfill site sold for residential development.

Option 2a – Energy recovery on site, landfill void space free for reuse.

Option 2b – Energy recovery on site, landfill site sold for residential development.

For each option, high, middle and low (best outcome, mid outcome and worst outcome) inputs were

modelled, based on a range of costs and revenues identified for each component of the model.

Printouts of the model and tables of assumptions are provided in Appendix 5. The modelled costs,

revenues and profits are detailed in Table 2.10.

Figure 2.1 – LFM operations used in fictional Scottish Landfill economic model

Mined material

Hand picking/mechanical

grab

Oversized, incompatibles

and inerts

Shredder

Trommel Soils

Magnet Ferrous metals

Drum Separator

Light and medium fractions (paper, plastic,

organics, textiles and wood)

Eddy current separator

Non-ferrous metals

Heavy fraction (C&D,

stones and glass)

Landfill

Re-used at landfill

Recycled

Recycled

Crushed and used on

site

RDF use off site

Energy recovery onsite


Table 2.10 Indicative economic model of LFMR in Scotland for a hypothetical ‘typical’ landfill.

Option 1a (RDF export & landfill reuse) 1b (RDF export & sale of land) 2a – energy recovery at landfill,

reuse of landfill

2b – energy recovery at landfill,

sale of land

Costs:£

millions

Best

outcome

Mid

outcome

Poor

outcome

Best

outcome

Mid

outcome

Poor

outcome

Best

outcome

Mid

outcome

Poor

outcome

Best

outcome

Mid

outcome

Poor

outcome

Investigation,

planning &

design

£0.5

£1 £1.5 £0.5

£1 £1.5 £0.5

£1 £1.5 £0.5

£1 £1.5

Opex

(excavation &

separation)

£32.5 £48.8 £65 £32.5 £48.8 £65 £32.5 £48.8 £65 £32.5 £48.8 £65

Capex

(excavation &

separation)

£5 £7.5 £10 £5 £7.5 £10 £5 £7.5 £10 £5 £7.5 £10

Landfill costs £6.5 £6.5 £6.5 £6.5 £6.5 £6.5 RDF gate fees

&

transportation

£17.1 £17.1 £17.1 £17.1 £17.1 £17.1

Opex energy

(recovery)

£4.6 £6.1 £7.6 £4.6 £6.1 £7.6

Capex energy

(recovery)

£10 £12.5 £15 £10 £12.5 £15

SUB TOTAL £55 £74.3 £93.5 £61.6 £80.8 £100.1 £52.6 £75.8 £99.1 £59.1 £82.3 £105.6


Option 1a (RDF export & landfill reuse) 1b (RDF export & sale of land) 2a – energy recovery at landfill,

reuse of landfill

2b – energy recovery at landfill,

sale of land

Revenue &

Savings:£

millions

Best

outcome

Mid

outcome

Poor

outcome

Best

outcome

Mid

outcome

Poor

outcome

Best

outcome

Mid

outcome

Poor

outcome

Best

outcome

Mid

outcome

Poor

outcome

Avoided costs

that would

have been

incurred in the

35 years

leading up to

environmental

permit

surrender.

£0.37 £0.37 £0.37 £0.37 £0.37 £0.37 £0.37 £0.37 £0.37 £0.37 £0.37 £0.37

Income from

recyclables

£8.7 £8.7 £8.7 £8.7 £8.7 £8.7 £8.7 £8.7 £8.7 £8.7 £8.7 £8.7

Energy sales £19.8 £13 £6.2 £19.8 £13 £6.2

ROCs £37.3 £21.4 £5.5 £37.3 £21.4 £5.5

Reuse of void

space

£4.4 £4.4 £4.4 £4.4 £4.4 £4.4

Sale of land £22 £17.2 £8.5 £22 £17.2 £8.5

SUB TOTAL £13.5 £13.5 £13.5 £31.1 £26.3 £17.6 £70.5 £47.9 £25.2 £88.2 £60.7 £29.3

TOTAL PROFIT -£41.5 -£60.8 -£80 -£30.5 -£54.5 -£82.5 £18 -£28 -£73.9 £29.1 -£21.7 -£76.3


2.3.5 Summary of economic implications of landfill mining in Scotland

The economic analysis presented in Section 2.3.4 is based on a hypothetical scenario, where best

attempts have been made to consider a ‘typical’ Scottish landfill. Furthermore, the assessment is

based on many assumptions and variables. For these reasons, it is necessary to acknowledge that the

assessment is a relatively simplistic and approximate method of determining the likely overall effect of

a range of possible costs and revenues associated with a LFMR project in Scotland. In addition, where

comment is made in this report in relation to economic considerations discussed by other authors, it

should be noted that these authors also often note similar limitations in relation to their findings.

The assessment has not considered every possible LFMR project, but has focused on four realistic

options:

Option 1a – RDF exported for use off site, landfill void space free for reuse.

Option 1b – RDF exported for use off site, landfill site sold for residential development.

Option 2a – Energy recovery on site, landfill void space free for reuse.

Option 2b – Energy recovery on site, landfill site sold for residential development.

In all cases, the assessment has considered that the process removes metals for subsequent re-

melting, generating a revenue in doing so. Everything else is either reused on site, landfilled on or off

site or used to form an RDF for use on or off-site. There are other possibilities, such as the use or sale

of soil and hardcore for use elsewhere, or the use of plastic for subsequent manufacture of products.

However, the use of soil on site is considered the most likely scenario for a LFMR project in Scotland

and it is considered most likely that plastic would form part of an RDF. Subject to the nature and

amount of these materials present in the landfill, this may not be the case. However, this assessment

is based on the scenarios considered most probable.

Whilst available LFMR literature does describe projects where offsite use of soils, including as fill and

growing media, has taken place, on-site use is most common. Soil has been used as growing media in

Israel in the 1950s and in China. Since many landfills involve filling of a void, as opposed to land raise,

it is likely that the replacement of some material as fill will be advantageous for subsequent

redevelopment of the land. If future landfilling is to take place, the on-site use of the separated soil as

daily cover material will be highly beneficial to the landfill operator. Finally, the use of soil off-site, in

Scotland, is likely to restricted by quality and regulatory implications associated with end of waste

criteria and environmental permitting. Such implications may not have featured in decision making in

some of the projects undertaken in other countries.

The economics of plastic separation for re-manufacture are unlikley to be favourable. The assessment

assumes the plastic quantity present in the hypothetical typical landfill is 59,800 tonnes. As stated

above, this plastic is likely to have little or no value other than possibly as an RDF. However, if this

was virgin polymer its value would be high. At the time of writing, global polymer prices are very high.

One website article reviewed, dated 31 August 2012, (www.business-standard.com) noted

international polyethylene prices are around $1,250 per tonne (£774). Taking this high virgin polymer

price and including it in the economic assessment (Option 1a- mid outcome) as a recycling revenue,

assuming separation efficiency was 100%, whilst at the same time removing the cost of RDF export,

returns a relatively low profit of £2.5m. However, the plastic from a LFMR will not have virgin polymer

value, will undoubtedly involve increased processing costs to separate and clean, and will not be

100% recovered. It is considered that the only currently viable option for plastic is redeposit in the

landfill or use within RDF.

http://www.business-standard.com/


The outcome of the economic assessment is that, for the typical Scottish landfill, LFMR is not

economically viable for most scenarios considered. The exceptions are with ‘best outcome’ inputs and

options where energy recovery is undertaken at the landfill, e.g. Options 2a and 2b.

The Capex costs for the thermal treatment plant have been selected based on numbers quoted by

other authors and with reference to a previous study undertaken by Ricardo-AEA on behalf of WRAP.

These numbers have been scaled down from figures associated with larger facilties. In reality, due to

economies of scale, smallscale thermal treatment plants are comparatively expensive. It is considered

that an ‘Option 2a’ or ‘Option 2b’ LFMR scheme is likely to be more viable for larger landfills, and

those with a higher content of material suitable for use as an RDF.

Although based on a simplistic and approximate approach with a high reliance on assumptions, this

assessment does reflect findings in LFMR literature, as summarised in Section 2.1 and 2.2. In

particular, the planned Remo landfill LFMR project in Belgium is considered, by those intending to

undertake the project, to be economically viable. The Remo landfill project centres around on-site

gasification of RDF, has better quality waste than considered in this economic assessment, and is a

much larger landfill. The Remo landfill project is expected to be operational for over 20 years, and is

expected to process 100,000 tonnes per annum.

2.3.6 Technical issues

Modern-day LFMR approaches are in their infancy, developed from numerous trial-and-error attempts

using current earth materials handling and management technologies and separation technologies

used elsewhere in the waste management industry and in other industries.

From a technical perspective, an effective LFMR project is dependent on:

A thorough understanding of the materials to be mined, including their variability and nature.

The effective selection/use of the appropriate technologies.

Product output specifications.

Contingency planning.

To determine feasibility, or select the most appropriate approach, a review of the historic landfill

operations and wastes received, along with interviews with landfill personnel, should first be

conducted. Next, a representative waste characterisation should be performed using a combination of

non-invasive and investigatory methods such as ground-penetrating radar (GPR), test pit sampling,

and/or borehole analyses to estimate composition (types of waste, density, moisture content) by

location. Finally, it should be determined whether or not the test samples collected will, with or

without further processing, meet the required product specifications.

2.3.6.1 Technology Overview

Listed below are a range of technologies that could potentially be employed in a LFMR operation.

Whilst most of these technologies are currently used within the waste management industry, many

are unproven, or little proven, in the application of LFMR. In comparison to waste shortly after the

point of generation, landfilled waste will often be compacted, degraded, mixed, intertwined and often

wet. Furthermore, shredding and separation equipment will most likely operate at different

efficiencies, and degrees of success, for waste from different landfills.


Excavation

Trackhoe and backhoe excavators

Bulldozers

Grappling Hoes

Size Reduction/Shredding

Hammermills - vertical and horizontal shaft

Shear shredder

Rotary, guillotine and scissors-type shears

Grinders - roller, disc-mill, ball mill

Flail mill

Wet pulper

Knife mill

Air Technologies

Windshifter

Drum separators

Air classifiers

Air knife

Screens

Trommel

Vibrating

Disc/star

Ferrous Metal Separators

Overband magnets

Drum magnets

Head pulley magnets

Non-Ferrous Metal Separators

Eddy current separators

Handling Equipment

Front-end loaders

Grapples

Conveyors

Forklifts

LFMR projects undertaken around the world to date have most commonly employed excavators,

screeners, trommels, shredders, grinders and chippers for removing and sorting materials from

landfills. More advanced separation technologies are less proven in the application of LFMR.

There are numerous potential approaches to LFMR, numerous potential variations of waste type,

quality and volume, numerous product specifications, and an even larger number of possible

combinations of equipment design and equipment combinations. A thorough examination of all of

these permutations and combinations is not appropriate for this high level scoping study. Instead,

provided below, is a short description of some of the technologies, how they might be applied and

their relative merits.

LFMR processes considered in this study are grouped as follows:

Excavation/ waste removal.

Size-reduction.

Screening.

Air technologies.

Metal separation.

Ancillary equipment such as conveyors, chutes, and controls are not considered.

2.3.6.2 Excavation/ waste removal

For most LFMR projects, the excavator is probably the most important piece of equipment required for

waste removal and handling. It is efficient, relatively low cost, can move high tonnages of materials

quickly, and can operate over many terrain types.

Following excavation, mobile or stationary grapples and/or front-end loaders and trackhoes are

typically used to organise the excavated materials into manageable stockpiles and separate out bulky

material, such as appliances and lengths of steel cable. This equipment is also used to load the waste


separation equipment. Once separated or processed, the loaders are used to pick up and transport

the waste and products to designated areas. Front-end loaders are also used for exracting waste from

the lower levels of deposits, or stockpiles. Bulldozers are also used in the excavation and waste

handling operations.

Landfilled wastes can be excavated as follows:

From the top, working downward in “lifts” (e.g. typically 3m per lift).

From the bottom, with a front loader removing sides and faces.

Waste is removed following removal and stockpiling of top cover soils/ capping. If leachate/

groundwater interferes with the excavation procedure, the level can be lowered by pumping to allow

dry excavation. This in itself requires prior planning as the leachate/water will need to be managed,

and potentially treated.

The volume excavated per day will depend on the numbers of equipment used and the throughput of

the waste separation processes. For a site with a daily excavation rate of 8,500 m3/day, the following

equipment numbers are typical:

Excavators (4)

Landfill trucks (12)

Grinders and screens (2)

An excavator can typically extract up to 70 to 90 m3/hr from depths of up to 7m.

As extraction activities approach the natural ground or liner system, special care has to be exercised

to prevent liner damage or escape of leachate.

2.3.6.3 Size reduction

Size reduction typically follows excavation and is undertaken to allow ease of subsequent material

handling and sorting.

Industrial grinders and shredders vary in many ways, according to the function they perform.

Appropriate selection is important to minimise damage to equipment and downtime. In mechanical

separation plants, downtime due to shredder breakdowns/maintenance is commonplace.

When deciding upon appropriate size reduction trechnology, it is necessary to carefully consider the

waste it has to handle.

In operation, it is necessary to ensure that operators excavating and moving wastes are diligent in the

removal of incompatibles wastes, in particular large solid metal objects. This will minimise breakdown

and downtime.

Shredder mechanical elements can be expected to require frequent rebuilding and replacement due to

the tough and abrasive nature of the materials normally found in mixed waste. Components of the

size reduction device that are subjected to the extensive and intensive wear and tear are the

hammers (or cutters) and the grate bars, where present. This is to be expected because these

components are in direct and continuous contact with wastes. As landfilled waste typically contains

high levels of sand and grit abrasive wear can also be expected.


In most cases, primary size reduction is usually to a minimum particle size of about 10 cm, considered

a “coarse” size. If primary shredding is designed to shred to a fine particle size, subsequent screening

becomes less effective, and shredder damage is more likely to occur. In many cases, the shredding is

more of a ‘tearing’ action, for example to break-up compacted wastes or large bags of waste.

Secondary size reduction, or re-grinding/shredding, is typically used where a particle size of less than

10 cm is specified, for example in the production of some forms of RDF or glass cullet. As such, this is

likely to occur towards the end of process for such materials. Size reduction also benefits subsequent

recovery of ferrous and non-ferrous metals.

For many materials, the best shredder type may be low-speed models or multiple shaft machines with

interlocking cutters or cams with very high torque. Plastics with low melting points will generally need

to be shredded at relatively low speeds, or cut, to avoid clogging machinery.

Shredder throughput capacities are highly variable, but many industrial size shredders will readily

handle throughputs likely to arise during a LFMR operation, typically up to 100 tonnes/hour.

Shredding operations can create dust as well as give rise to high levels of noise. Shredding or grinding

equipment may need to include dust containment and removal systems, as well as acoustic cladding

and/or housing within a building.

2.3.6.4 Screening

Screens are used to separate wastes by size, with material passing through the screen being known

as ‘undersize’, or ‘fines’, and that which does not is known as ‘oversize’, or ‘overs’. Some screen

arrangements allow for sorting to a greater degree, thus creating a ‘midsize’ fraction in addition.

There are several designs of screens. Screens commonly employed in waste management are flat

vibrating screens, trommel screens and star screens.

Screens could be employed at different stages of the process, subject to the nature of the waste and

the required product specification. At different stages, the choice of design is subject to the nature of

the waste feeding the screen. For example, a trommel screen might be employed near to the front

end of the process where the feed is compacted, and highly irregular and varied. However, a looser

drier, more granular waste, which could be encounterred further on in the process, might be more

suited to a vibrating flat screen. Such a screen could, for example, be used for the processing of glass

extracted from the landfilled waste. Flat bed screens tend to blind when loaded with wet wastes.

Trommel screens have commonly featured in LFMR projects undertaken to date around the world,

principally as a way of separating soil from the wastes. It is reported that operators of LFMR projects

prefer trommel screens over flat vibrating screens.

A trommel screen is an open ended cylindrical screen, or drum, which is orientated on its side, with

one end slightly elevated above the other. The drum rotates along its central axis on trunnion wheels.

Bars or ridges are commonly placed running parallel along the length of the inside of the drum at

intervals around its circumference. As waste enters the drum it is thrown around inside it, the drums

or ridges aiding in this process. This action helps to separate wastes which are clumped together, or

intertwined, which is to be expected for wastes excavated from a landfill. Small wastes pass through

the screen, whilst larger wastes remain inside the drum. Since the drum is situated on a slight incline,

the wastes in the drum, which are too large to pass through the screen, eventually exit at the far end

of the drum. The size of the screen influences the materials that are separated. The nature of the

waste and its volume will dictate drum diameter and length. The higher the throughput, the greater

the diameter required. For wastes that may require a greater degree of breaking-up, a longer drum

may be preferred. Other design factors include speed of rotation and angle of inclination, as well as


nature of the screen itself. Screens can be interwoven wire mesh or punch plate and round hole or

square hole. Each has its relative merits subject to the waste being treated. Screens can

blind/block/foul and so brushes are often located running parallel along the length of the outside of

the drum to remove materials, such as textiles, which are blocking the screen. Further to this, it is

often necessary for operators to stop the trommel and to manually remove trapped material.

A trommel with a single screen size will generate two waste streams, that passing through the screen

and that which exits at the far end of the drum. A trommel with two screen sizes will create three

waste streams. In such a situation, the first half of the trommel drum will contain a screen size

smaller than the second half.

Trommels are particularly useful for separating fine organic materials and soils from other wastes. For

this reason, they are commonly employed on LFMR projects where soils can typically make-up half of

all waste. However, trommels are widely used in the waste management industry for a wide range of

waste streams, wherever there are materials with distinct size differences.

Disc screens, or star screens, are a flat bed of upright discs, or star shaped discs, mounted on

horizontal shafts. The discs/stars on each shaft are located so they are offset and interlocking with the

discs/stars on the next shaft along. This arrangement is somewhat like a table football game, whereby

there are many players (discs/stars) on each shaft and with each row of players (shaft with discs/stars

mounted along its length) being located close to the next one along. Waste enters on top of the bed

of discs/stars and the small wastes pass through the gaps in between the discs/stars, whilst the action

of the rotating shafts and inclination of the beds encourages the larger wastes to progress over the

bed.

The authors have found no reference to the use of disc/star screens in LFMR projects undertaken

around the world to date.

Screens can be constructed to any size, and can be readliy designed/purchased to accommodate

throughputs of waste to be expected at a LFMR operation. All types of screens are available as both

mobile and fixed arrangements.

When appropriately designed and set-up correctly, screens are relatively simple and robust in

operation. Periodic manual cleaning will be required and damaged screens will need replacing, as will

worn bearings and worn brushes on trommel screens. However, in comparison to other types of

separation equipment, screens are relatively low maintenance.

2.3.6.5 Air technologies

Air technologies can take many forms, including windshifters, separation drums, air classifiers and air

knives. All air technologies rely on light, low density, fractions of waste being separated from heavy,

high density, fractions in a stream of air.

A windshifter is typically employed at the head of a conveyor, from where light material is either

sucked or blown from the flow of waste exiting the conveyor. Windshifters are commonly used in

waste separation plants, in a range of applications treating a range of wastes. In many cases, wastes

entrained in the flow of air are removed via an expansion chamber wherein the velocity of air is

reduced allowing the waste to settle out by gravity.

A separation drum is a contained unit in which various grades of waste are removed by a series of

varying flows of air. As with windshifters, a separation drum utilises expansion chambers to settle-out

wastes.


An air classifier uses vortex flows and centrifugal force to separate out materials, working on a

cyclone principle. These systems are best suited to fine or granular material. This technology is widely

used in industry, including the waste management industry where it is typically employed within

composting operations.

Air knives are curtains of high velocity air, typically acting vertically or sideways on material passing

along a conveyor. Widely used in industry, including the waste management industry, air knives can

be used to strip-off light material and also to remove moisture from materials.

Although sometimes discussed within LFMR literature, Ricardo-AEA are not aware of examples where

air technologies have been employed in a full scale LFMR project. Whilst air technologies are widely

used elsewhere in the waste management industry, they do have their limitations and their application

to LFMR may be limited to certain stages in the process wherein the waste has been suitably pre-

conditioned.

Air separation technologies work best where the waste is uniform in composition, loose and contains

similarly sized particles of materials of different density. Separation is hampered by waste which is

highly variable, clumped together, wet, entwined and of varying sizes. Balancing the flow of air to suit

the waste can be a challenge and can result in all or nothing being removed from the waste stream.

Trying to extract only one material out of plastic film, textiles and paper can prove difficult since they

are all low density materials.

It is considered air technologies could potentially be employed on a LFMR project, particularly one

creating RDF, but Ricardo-AEA consider that separation efficiency may be poor given the nature of

excavated landfill waste. Inclusion of air technologies within the design of a LFMR operation should be

undertaken with great care, a detailed understanding of the waste to be treated and following suitable

trials.

2.3.6.6 Metal separation

Metal separation within the waste management industry includes removal of ferrous and non-ferrous

metals. Removal efficiency is typically high and equipment robust. Ferrous metal recovery has been

employed on previous LFMR projects.

Ferrous metal removal is normally undertaken by using drum magnets or overband magnets. Drum

magnets sometimes form the head pulley on conveyor systems.

In operation, an overband magnet is placed over a flow of waste. The magnet, which can be

permanent or electromagnetic, is encircled by a single conveyor belt which runs in a continuos loop

around the magnet. The magnet lifts ferrous metal from the flow of waste, whish is attracted to the

conveyor running over the surface of the magnet. This conveyor then moves the metal object,

normally perpendicular to the flow of waste beneath it, until a point beyond the magnet, whereupon

the metal object drops into a chute or container located off-centre to the main flow of waste.

Overband magnets are simple and easy to maintain and can be portable. Their main disadvantage is

that they are not suited to large metal objects. Large metal objects would require a strong magnet,

the result being damage to the overband magnet conveyor fabric and an inability for this conveyor to

move freely.

Drum magnets are better suited to heavy ferrous metal objects. These arrangements comprise a large

diameter metal drum which rotates around a magnet acting upon a limited area of the drum. Placed in

proximity to the flow of waste, ferrous metal objects are removed from the flow of waste, whereupon

they stick to the drum until such point as they rotate beyond the influence of the magnet and drop off


into a chute or container. These arrangements do not involve a conyeyor, as with overband magnets,

meaning that the magnet can be of any strength. As such, these arrangements are more robust.

Drum magnets can be installed as head pulleys on waste conveyor systems. This is quite different to

the overband magnet arrangement. A head pulley magnet does not attract a ferrous metal object

from a flow of waste, since the entire flow of waste passes over the magnet. However, whilst non-

ferrous wastes drop from the end of the conveyor, ferrous metal objects rotate around the head

pulley to its underside until such point as it passes beyond the magnet, whereupon it drops into a

chute or container. Since there is no impact of metal objects hitting the conveyor, conveyor damage is

not an issue.

The term ‘drum separator’ is sometimes used to refer to drum magnets, which could lead to confusion

with the ‘drum separators’ discussed under ‘air technologies’.

Ferrous metal recovery from excavated landfilled waste should be a straight forward operation. The

separated metal may contain greater levels of contamination in comparison to metal extracted from

non landfilled MSW, e.g. in a dirty MRF, due to the compacted nature of excavated landfilled waste.

Eddy current separators are used on waste management plants for the removal of non-ferrous metals,

most commonly aluminium and copper. Waste passes over a drum, or conveyor pulley, in which a

rapidly spinning rotor creates an alternating polarity magnetic field which repels metals. The metals

are repelled from the pulley/drum and thrown over a splitter arrangement allowing separation from

the rest of the material, which drops from the end of the conveyor into a separate chute. This process

requires prior removal of ferrous metals and requires a well separated and evenly presented thin layer

of waste. Any material adhering to, for example, an aluminium can could weigh it down sufficiently to

prevent it from being separated effectively. Similarly, any loose plastic film lying on top of the can can

prevent it from being effectively thrown over the chute partition splitter. Whilst separation can be

effective when handling suitably pre-prepared non landfilled MSW, its effectiveness is likely to be

much diminished when treating excavated landfilled waste. This technology is, to the best of the

authors knowledge, largely unproven in the application of LFMR. Whilst it could prove useful, its

success would depend on how the waste is processed prior to the eddy current separator.

2.3.7 Environmental issues

LFMR can give rise to significant positive environmental impacts, including:

Removal of potential source of pollution. By removing the waste, or components of it, the

potential for leachate and gas release to the environment is diminished. Leachate migration can

contaminate surface water and groundwater. Fugitive gas emission from the landfill surface to

atmosphere is a contributor to global warming and can give rise to odour issues and dense gases

can accumulate in low ground giving rise to risk to human health. Lateral migration of gas through

surrounding soil can accumulate beneath or within buildings with potential for explosion,

asphyxiation, odour and long term risk to human health. In addition, lateral migration of gas can

give rise to vegetation stress. Although LFMR is normally undertaken once landfills have achieved a

reasonable degree of stabilisation, low volumes of gas are still likely to be being generated, and

will most likely continue to do so for many years if LFMR does not take place.

Retrofitting liners and removing hazardous materials. If landfill operations are to continue,

or recommence, liners and leachate collection systems can be installed at older landfills where not

present. These systems can be inspected and repaired if they are already installed. Also, any

hazardous waste can be removed and managed in an appropriate fashion.

Extending landfill capacity. LFMR can extend the life of a landfill by recovering void-space.

Void-space is recovered as materials are removed, for recycling and/or energy generation, and

through improved compaction of any waste replaced. Most waste deposited in a landfill is


compacted using appropriate mobile plant (compactor), following tipping. Over time, as waste

degrades, the waste mass sinks and voids occur as a result of bridging and uneven settlement.

These voids are eradicated as waste is excavated, sorted and placed back into the landfill. In

addition to commercial benefit, the effect of extending landfill capacity gives rise to environmental

benefit by avoiding impacts associated with development and construction of a new landfill facility.

Such impacts include material consumption, material transportation, energy required in

construction and potential impact of a new development upon the local environment, including

impacts upon residents of nearby properties.

Reclaimed soil. If landfill operations are to continue, or recommence, reclaimed soil can be used

on site as daily cover material, thus avoiding the cost and transportation impacts of importing

cover soil. In addition, the soil could be put to other uses subject to local market demand and

regulatory considerations.

Producing energy. Combustible waste can be used to generate energy at a thermal treatment

plant, reducing reliance on fossil fuels.

Recycling of materials. Other excavated waste can be processed to remove valuable

components, such as steel and aluminium, for subsequent reprocessing.

Freeing-up land for other uses. Removal of all waste, or all active waste, is likely to give rise to

earlier surrender of the landfill permit, with financial savings in long term management, and

potentially frees-up the land for other uses quicker. This return of the land to beneficial use will

potentially remove the burden of development elsewhere. It should be noted that removal of all

waste does not automatically give rise to permit surrender. However, the conditions required to

achieve permit surrender are likely to be easier to achieve.

There are also inherent environmental risks and concerns associated with LFMR, many similar to those

encountered during routine landfill construction and waste disposal.

The environmental permit application will be required to fully address all potential risks in advance of

a LFMR operation commencing. Many of the conditions present at the landfill and its surroundings will

be unique to the specific landfill, and specific to the age of the waste being excavated.

Environmental hazards and typical mitigation measures are discussed below. Most risks are reduced

by minimising the size of the exposed working face and excavating waste in a pre-planned methodical

manner.

Managing hazardous waste that may be uncovered during reclamation operations. Hazardous

wastes are likely to be more prevalent at older landfills that were in operation at a time when

waste disposal practices and waste acceptance criteria were not as robust, or well regulated, as in

the present day. Such wastes may be subject to special handling and disposal requirements to

mitigate risk to the environment and human health of workers, nearby residents and other

members of the public. Management may include:

Development of appropriate human health and environmental risk assessments.

Development of management plans, including planning for the unknown, e.g. exposure

of a waste that was not anticipated.

Training of staff.

Provision of appropriate personal protective equipment (PPE) for site workers.

Provision of appropriate set-aside areas and appropriate containers for storage of waste.

Provision of migration barriers for dust and potentially windblown material, which could

include measures such as water mists/sprays, screens and netting.

Provision for re-interment of certain wastes elsewhere on the landfill where their

exposure presents an immediate risk, e.g. provision for the rapid re-interment of

asbestos containing wastes.


In planning for the undertaking of a LFMR operation, extensive research into the nature of

landfilled wastes is essential, as is well documented in available LFMR literature. The extent of

required management methods will be subject to the nature and quantity of hazardous waste

expected. The presence, nature and extent of hazardous waste could be sufficient to prevent a

LFMR operation from taking place on the basis of degree of risk, or resulting expense. Should

hazardous waste be uncovered that was not anticipated, or is found to be present in greater

quantity than was envisaged, substantial down-time could arise, potentially bringing a close to the

LFMR operation.

Controlling releases of landfill gases and odours

Waste excavation raises a number of potential problems related to the release of gases. Methane

and other gases, generated by decomposing wastes, can cause explosions, fires, odours and risk

to human health. Hydrogen sulphide gas, a highly flammable and odorous gas, can be fatal when

inhaled at sufficient concentrations.

The presence of gas generating wastes, the quantity present and the age of the waste are key

factors that dictate the volume of gas being generated. Many LFMR projects undertaken to date

have been undertaken on relatively old wastes, typically over 25 years old. This is because the

decomposition of waste will be advanced, giving rise to low levels of gas generation. The younger

the waste and the higher the production of gas, the greater the risk of odour issues and explosion.

Ensuring the operation takes place on suitably stabilised wastes is a key management method.

However, low levels of gas can still give rise to issues, in particular the risk of accumulation to

explosive or asphyxiating levels within confined structures, including beneath and within buildings.

Subject to a number of factors, the explosive limits of methane are generally between 5 and 15%.

Landfill gas is typically around 50 to 60% methane, although it is variable, especially in older

wastes. As waste is excavated, the gas escapes and is rapidly diluted in the open air. The greatest

risk is that escaping gas builds up in a confined space, bringing with it a risk of explosion. As

reported in literature, gas monitors with alarms are used to monitor levels of gas, including

methane, at the location of waste excavation. The location and design of any buildings or

structures in proximity to the operations will have to be undertaken with consideration to the risk

of the accumulation of landfill gas and afforded appropriate monitoring. This would be expected for

any building on or in proximity to a landfill, irrespective of whether or not LFMR is taking place.

However, consideration should be given to the fact that the risk may be increased as a result of

changes in the rate and manner of gas release as a result of the LFMR operation.

Controlling releases of liquids and leachate

Suitable containment and drainage will need to be afforded to all areas used for stockpiling and

processing wastes. It is likely that any surface water runoff from these areas will either need to be

collected and treated, or diverted into the landfill mass.

Consideration will need to be given to any changes in surface water run-off that may arise as a

result of changing the landfill form.

Consideration will need to be given to any damage to leachate collection and drainage systems

that may result from the excavation process. Poor drainage could have waste mass stability

implications.

To minimise issues associated with excavating beneath the leachate or groundwater table, and

associated handling of sodden wastes, it may be necessary to pump the level down prior to

excavation. This would require appropriate management of the pumped liquids.


Having removed any capping materials that may be present, rainwater entry and thus leachate

generation is likely to increase. For this reason, minimisation of the exposed working face can be

beneficial.

In addition to the potential risk of escaping liquids and leachate, management methods for dealing

with high leachate or groundwater levels could significantly add to the cost and complexity of the

project.

Controlling releases of dust. Dust generation is a significant, but manageable, risk at any active

landfill operation, whether or not LFMR is taking place. Dust can result from the excavation and

processing of wastes, as well as traffic movements on site. Water bowsers to dampen roads in dry

conditions, or friable wastes, is an effective mitigation measure. Dust abstraction and collection on

separation and sorting equipment, and possibly containment within a building, may be necessary.

Where asbestos is, or is expected to be, encountered special measures are likely to be required,

such as the use of fine spray mists. Finally, stopping operations in high winds may be necessary at

times.

Controlling subsidence or collapse. Excavation of a landfill area can undermine the integrity of

adjacent cells, which can sink or collapse into the excavated area. Such events could release

contaminants into the surrounding area, as well as cause damage to engineered structures and

risk of injury to site operators. This can be controlled by ensuring the nature of the waste,

including its compaction, presence of voids, variability, stability, moisture content and levels of

leachate or groundwater are understood in advance of the operation. The working method can be

developed with consideration to these factors. Limiting the depth of excavation for any one lift is

likely to be a key management method.

In addition to the above, the operation will give rise to noise, may attract vermin and is likely to

involve additional traffic movements on the local road network. In addition to conjestion and impact

on local air quality, vehicles leaving site could spread mud onto the highway, unless appropriate wheel

wash and vehicle washing facilities are available. These are risks that are well understood by landfill

operators and regulators, and apply equally to landfilling operations as they do to LFMR operations.

Environmental risks can be managed if considered in advance of the operation and appropriate

mitigation measures designed and implemented in discussion with regulators. Pertinently, these risks

would require addressing in an environmental permit application and the regulator, SEPA, would

require all risks are identified, appropriately assessed and mitigation measures put in place, where

necessary, prior to permit issue and commencement of operations.

When scoping and planning a LFMR project for a specific landfill, it is necessary to fully establish the

‘conceptual model’ of the landfill and its surroundings. The conceptual model is the full understanding

of the waste, the engineered structure of the landfill and the surroundings, including potential

receptors to pollution, contamination or nuisance. This includes any potential migration pathways

within the waste mass and surroundings, such as drains, ditches, buried services, leaks in any liners,

permeable soils or faults etcetera in the surrounding geology. It will be necessary to study any

available gas, leachate and groundwater quality and water level monitoring results from in waste and

perimeter boreholes. This will assist in establishing any possible impacts upon water quality and the

local hydrological and hydrogeological regimes.

Subject to location, there may be sociological issues arising from perception of these risks from

nearby residents or other stakeholders in the local environment. This is discussed further in Section

2.3.9.


2.3.8 Regulatory issues

Regulatory issues are fundamental to any future LFMR project in Scotland for the following reasons:

Failure to obtain the required authorisations would prevent a project from taking place.

Failure to comply with conditions within an authorisation could potentially bring a halt to an

operation.

Making applications for authorisations involves cost and time implications.

Maintaining and surrendering a permit involves cost and time implications.

The regulator can influence the manner in which the operation is undertaken, in particular via

conditions within a permission or permit.

Regulatory requirements, such as engineering requirements or methods of working, could impact

upon the economics of a project, potentially preventing it from taking place.

Given the significance of these potential occurrences, it is highly beneficial to involve regulators in

early discussions when considering whether or not to undertake LFMR at a particular landfill.

The required authorisations and implications of associated conditions will be specific to each individual

LFMR project. It should be borne in mind that LFMR experience in the UK has been limited to date and

has not involved resource reclamation and recovery. As such, regulators as well as operators will not

be able to benefit from the familiarity from having ‘been through it already’. In theory, the concept of

LFMR is sound in terms of sustainability and so, in theory, there should be a presumption in favour of

a project. However, the regulator is there to ensure operations are undertaken in accordance with

relevant legislation and undertaken in a manner that affords protection to the environment and

human health and avoids nuisance. Consideration of regulatory issues is intrinsically linked to

consideration of environmental, sociological, technical and economic issues. These issues are

discussed elsewhere within Section 2.3.

Subject to the nature of the project, a future LFMR Project in Scotland is likely to be regulated by

SEPA via the permitting regime and many will also likely need to meet local planning requirements. At

present, environmental permitting in Scotland is primarily legislated for via the Pollution, Prevention

and Control (Scotland) Regulations 2000 (as amended) and the Waste Management Licensing

(Scotland) Regulations 2011. Under the first regime, PPC Permits are issued and Waste Management

Licences (WML) are issued under the second regime. The applicable regime is subject to the nature of

the waste operation taking place. In the case of landfills, operational landfills in the current day are

regulated under the PPC regime and many of the closed landfills under the WML regime, which was in

force prior to the introduction of the PPC regime. In future, it is intended that the two regimes merge

into a single permitting regime as has occurred in England and Wales.

Irrelevant of the specific type of authorisation, and which regulations it is required under, all

applications generally follow the same basic requirements as detailed below.

A description of the proposed activity including inputs and outputs, resources to be utilised,

infrastructure and equipment and how the operation is to be undertaken, including justification for

the selected infrastructure and equipment.

Production of a conceptual model of the site. This typically comprises identification of potential

sources of pollution or nuisance (point source or fugitive), potential receptors of any emission or

pollutant and identification of pathways that connect the two.

Production of risk assessments to assess potential impacts identified in the conceptual model.

Identification of any abatement or mitigation techniques to reduce or eliminate risks.

Environmental monitoring plans

Restoration plans


Aftercare plans (landfill)

Applications for landfills normally entail amenity, stability, gas and hydrogeological risk assessments.

The requirements for non-landfill waste applications will depend on the nature of the proposal but,

amongst other considerations, typically include noise, odour, dust, emissions to air and water.

In order to surrender a licence or permit for a landfill, it is necessary to demonstrate that the landfill

no longer poses a threat to the environment and that the requirements of the landfills closure plan

have been met. For any other facility/installation, it is necessary to demonstrate that ground and

groundwater conditions at the site are of a quality equal to that at the start of the permit and that any

contamination that has occurred has been remediated.

The exact requirements will vary subject to the nature and location of the activities taking place.

Whilst there is generally a good degree of commonality between a planning application and a permit

application, there are notable differences. For example a permit application will involve less detail on

matters such as visual impact, building fabric and colour, light pollution and suitability of and impact

upon the local road network. A planning application will involve less emphasis on matters such as

resource and energy use and detailed explanation and selection of technologies. A permit cannot be

issued without any required planning consents being in place. A planning consent typically includes a

condition to the effect that operation cannot commence without the prior consent of SEPA.

Future land use, post mining, would most likely be subject to planning permission. If that use is as a

landfill, it would need to operate under a PPC permit which would only be issued if the landfill met

modern engineering requirements as detailed in the Landfill Directive.

Provided below are selected pieces of information obtained from a paper, by Jonathan Atkinson of the

Environment Agency, included in the proceedings of the Global Landfill Mining Conference 2010

(Jonathan Atkinson, 2010).

‘The Environment Agency remediation statements make it clear that excavation of materials from a

non-permitted site is not in itself a waste activity. It is the further storage, treatment and disposal

or recovery that are waste activities that may fall under Environmental Permitting Regulations

permitting. If, however, the site has an existing permit, the permit will need varying.’

‘Excavating a landfill to create a void, if the site is permitted, does not guarantee immediate

surrender of the permit. There is still a requirement to show that any groundwater contamination

has been cleaned up/has no effect as per permit surrender guidance.’

‘……….it is the follow on activities that will be covered by relevant waste regulatory permits up to

the point of full recovery. So the sorting, screening, separation plant, the energy recovery facilities

and the onward transfer of recovered materials like scrap metals would all readily fall under the

existing permitting regime for waste management and duty of care, either as fixed facilities or

under temporary mobile treatment permitting.’

‘……….we have a clear starting point, but in a new context and application perhaps, modern

regulation is about “yes if” and risk based approaches, worked up with the regulators from an early

proposal point. This will allow us all to move forward in a positive framework rather than one with

negative mining or disposal perceptions.’

‘In line with our position statement on the CLAiRE Code of Practice – excavated materials can be

re-used on site and not be deemed controlled waste in that context if they are “suitable”. Any

treatment of excavated materials prior to re-use is a waste-treatment activity that is covered by a

relevant permit.’

‘Temporary treatment plants may be covered under mobile treatment permits and deployments’


These comments broadly apply in concept to Scotland. The Scottish regulatory regime is very similar

to that in England and Wales and the requirements of the EU Landfill Directive, EU Waste Incineration

Directive and EU PPC Directive apply in all EU member states. In particular, the reference to the

excavation of material and reuse on the site on a non-permitted site accords with principles within

SEPAs document ‘Land remediation and waste management guidelines’.

The particulars of the project are likely to be such that planning consent is required. This may require

an Environmental Impact Assessment (EIA) to be undertaken under The Town and Country Planning

(Environmental Impact Assessment) (Scotland) Regulations 2011. Under these regulations,

developments listed within and meeting criteria of Schedule 1 always requires an EIA and those within

Schedule 2 may require an EIA subject to certain criteria, including considerations detailed in Schedule

3. The details of the particular project should be discussed with the relevant planning authority to

ascertain whether or not EIA is required.

The development of a landfill is a Schedule 1 waste disposal activity. Any redevelopment of a closed

and mined landfill for future landfill purposes would therefore likely require an EIA. One of the

activities listed under Schedule 2 is ‘any change to or extension of development of a description

mentioned in Schedule 1’.

Open-cast mining where the surface of the site exceeds 25 hectares is listed in Schedule 1 to the

Environmental Impact Assessment (EIA) Regulations. The full wording of the listing is as follows:

‘19. Quarries and open-cast mining where the surface of the site exceeds 25 hectares, or peat

extraction where the surface of the site exceeds 150 hectares.’

Conceivably, landfill mining could be deemed ‘mining’. The regulations offer no definition of mining.

However, in separately stating ‘or peat extraction’ rather than it automatically being included in ‘open-

cast mining’, would infer that open-cast mining is something more specific than simply excavating a

material for subsequent use, which would include excavation of peat and excavation of landfilled

waste. Ricardo-AEA consider that the ‘mining’ referred to in the regulations applies to the extraction of

mineral deposits. It is considered that ‘landfill mining’ is an unfortunate term in this respect and that

the regulations were not made with specific consideration of landfill mining. The waste was landfilled

as a waste management activity and the excavation and further treatment of that waste is considered,

by Ricardo-AEA, to be a subsequent waste management activity rather than ‘mining’. To add further

weight to this point of view, ‘The Management of Extractive Waste (Scotland) Regulations 2010’ refers

only to mineral waste and defines extractive waste as follows:

“extractive waste” means waste produced from an extractive industry and resulting from

prospecting, extraction, treatment and storage of mineral resources and the working of

quarries, but does not include-….

These regulations define ‘mineral’ as follows:

“mineral resource” or “mineral” means a naturally occurring deposit in the earth’s crust of an

organic or inorganic substance, such as energy fuels, metal ores, industrial minerals and

construction materials, but excluding water.

These definitions are in line with those in the Directive on the management of waste from extractive

industries.

Irrespective of where a particular project may or may not fit within the EIA regulations, it is possible

that an EIA may be required and hence early discussions with the planning authority are important

when considering undertaking a LFMR project.

http://www.legislation.gov.uk/ssi/2011/139/contents/made


Given haulage costs, it is likely that the sorting and separation elements of a LFMR project in Scotland

would be undertaken on site. As detailed above, this will most likely require a waste management

licence/ permit. As also detailed above, where a licence/permit is currently in force for the landfill, this

will also most likely require varying.

Table 2.11 summarises the most likely regulatory requirements for a LFMR project in Scotland. Every

potential project should first be discussed with the planning and environmental regulators at an early

stage in the project planning.

Table 2.11 Overview of regulatory requirements

Landfill Potential licensing/permitting

requirements for LFMR project

Potential planning

requirements for LFMR

project

Old landfills pre-

licensing/permitting

Licence/permit likely to be required for sorting

and separation activities and subsequent energy

recovery, if undertaken on site.

A permit would be required for any future

landfilling activities at the site and the new

landfill would have to satisfy Landfill Directive

requirements.

Unless covered by an

existing consent, planning

consent is likely to be

required for the excavation

and processing of waste,

potentially with an EIA.

Unless covered by an

existing consent, planning

consent with an EIA would

be required if the site is to

be redeveloped for future

landfill

Landfills that are

closed and have

surrendered their

licence/permit

Closed landfills with

licenses/permits

The permit will require varying.

Subsequent sorting and separation activities

may require their own licence permit if they

cannot be accomodated under the landfill’s

licence/permit. Subsequent energy recovery will

require permitting, if undertaken on site.

Future landfilling activities would have to satisfy

Landfill Directive requirements.

Landfills with

licences/permits that

are being restored

Operational landfills

with permits

2.3.9 Sociological issues

Many stakeholders are likely to have an opinion on a LFMR project in Scotland. Local stakeholders are

likely to include nearby residents, schools, hospitals, businesses, farmers, local interest groups and

associations and users of the surrounding environment for its amenity value. In addition to these local

stakeholders that live, work and spend recreational time in the immediate area will be other

stakeholders at a local and national level, including organisations such as SEPA, SNH, RSPB, water

authorities, operators of airports etcetera. Listed below are a range of viewpoints which Ricardo-AEA

consider could be held by a range of stakeholders in a LFMR project.

Negative opinion of nearby residents, businesses, places of work and schools and hospitals based

upon concern over health, amenity and nuisance impact, property value and road congestion. This

could be exacerbated if it is intended to reuse the voidspace for future landfilling activities

following the LFMR operation.


Positive opinion of nearby residents, businesses, places of work and schools and hospitals based

upon removal of landfilled wastes. Removal of waste could be viewed as a process that

reduces/eliminates on-going risks and impacts upon health and environment. A resident may

perceive that a completed LFMR project could give rise to a positive impact upon property value

and subsequent redevelopment could be favoured over living in proximity to a landfill.

Local and national interest groups and users of the area for recreational purposes may have an

interest in the disruption to the landfill structure and habitat and, or, subsequent development.

This could be in relation to matters such as access rights or habitat and biodiversity, for example

ramblers and local ornithologists or local and national wildlife groups.

Any LFMR proposal that reduces loading of leachate to sewer is likely to be viewed positively by

the local sewerage undertaker.

Environmental pressure groups may view the resource recovery consideration in a positive light,

although thermal treatment plants often receive negative attention from environmental pressure

groups.

Regulators such as the local authority planning officers, local authority contaminated land officers

and SEPA officials may particularly welcome LFMR at a landfill which is giving rise to ground and

groundwater contamination.

It is impossible to consider every conceivable viewpoint that an individual or group might have and

views are likely to vary between individuals, groups and between similar stakeholders at different

landfills. The following considerations are considered by Ricardo-AEA as likely to influence opinion at a

specific landfill.

Whether or not landfilling or other waste management activities are currently undertaken at the

site. The extent of any negative opinion may be greater where a landfill has been closed for a

while and no waste management activities are currently undertaken. Most landfills in Scotland do

not have other waste management facilities associated with them.

The presence of, and scale, of habitation in proximity to the landfill, including residential and

business as well as schools and hospitals.

The scale and duration of the project. A long term LFMR operation may be viewed differently to a

small or short term proposal.

The proposed after use of the landfill, including the possibility of extending the life of the landfill.

Some stakeholders may not object to the LFMR operation itself, but may not like the proposed

after-use for the site. Conversely, the proposed after use of the landfill may be an attractive

element of the project to certain stakeholders.

In recent years, the proposed development of thermal treatment plants has often given rise to

adverse public opinion. A large-scale project could give rise to the construction of a thermal

treatment plant, if energy recovery features in the treatment solution and feedstock is sufficient.

Such a proposal could be met with more opposition than a proposal involving no thermal

treatment, or the utilisation of an existing off-site thermal treatment plant.

The sensitivity of the environmental setting in terms of proximity of sensitive habitats such as Sites

of Special Scientific Interest (SSSI), Special Areas of Conservation (SAC), Ramsar sites (wetlands of

international importance), national parks, local nature reserves and Areas of Outstanding Natural

Beauty (AONB).

Waste management development often meets with adverse negative public opinion from stakeholders

whom live, work, or spend leisure time within close proximity to the site. Many of the concerns that

can be expected to be raised, in relation to a LFMR operation, apply for the development of any new

waste operation. However, there are certain environmental and health risks that are different in

nature and extent to that of other waste operations, including new landfill development. Operators

intending to undertake a LFMR will have to fully evaluate, understand and control environmental and


health and safety risks. Engagement with all stakeholders will have to pro-active, thorough and

meaningful in order to address and allay stakeholder concerns, including regulators of the operation.

2.4 Conclusions

It is considered that landfill mining in Scotland is not likely to become a widespread occurrence,

principally due to economic considerations. However, in certain circumstances, it could be viable.

Landfill mining in Scotland is feasible, although viability is subject to a complex mixture of

considerations. Listed below are situations whereby a project may be viable.

LFMR involving onsite energy recovery at non-hazardous landfills where the waste being mined has

stabilised e.g. generating reduced quantities of gas and lower strength leachate. Where landfilling

has taken place in unconnected engineered cells, it is possible that LFMR could be undertaken at

discreet cells on active landfills that have been in operation for a long time. Economic viability will

be subject to numerous complex considerations, although waste quantity and composition are two

of the most pertinent. Waste from the mid 1960’s to the mid 1990’s is likely to yield the most

favourable results. Due to the capital costs associated with construction of small-scale thermal

treatment plants, economic viability is likely to be better at Scotland’s larger landfills.

LFMR with resource and off-site energy recovery might be feasible where wastes are to be

excavated anyway, assuming that the alternative is to pay for landfill elsewhere. This is not likely

to be commonplace and restricted to situations where waste is being excavated in order to relocate

it. Even though the LFMR operation may not be economically viable in its own right, the recovery

of soil for use as daily cover, the recovery of metals, and possibly lower gate fees for thermal

treatment of RDF, may help to offset some costs associated with the relocation exercise.

Excavation, shredding, screening and removal of ferrous metal, with sale of metal, recovery of soil

for use as daily cover and replacement and compaction of waste may be economically viable based

on the voidspace recovered. As the processing equipment used for such an operation is typically

mobile and can be leased, this could potentially be carried out on any size of landfill. This scenario

has not been assessed in this study, which has focused on maximum utilisation of recoverable

material. However, this has been undertaken at landfills in the USA with some reported success.

It is apparent that very few LFMR projects have been undertaken worldwide and that LFMR for

material and energy recovery is in its infancy. The main drivers for projects undertaken to date have

generally been for reasons other than material and energy recovery. LFMR is technnically feasible,

although advanced separation techniques are not well proven in the application of treating previously

landfilled wastes. Although discussed in literature, the reality of applying technologies such as air

classifiers or eddy current separators to the processing of excavated landfill waste is largely unproven

and not likely to be straight-forward. Since all projects require excavation, and most projects to date

have involved shredding and screening, these activities are well understood and proven.

LFMR is feasible from the perspective of environmental, regulatory and sociological issues. However,

all three considerations are capable of preventing a specific LFMR operation from taking place. This

does, however, apply to any waste operation. LFMR is not a simple operation to undertake and there

exists the potential to create significant environmental impact, health and safety risk and nuisance

risk. Whilst mitigation measures can be put in place, the cost of doing so could be prohibitive. If the

project has not been extensively thought through, and planning and permitting applications are below

the required standard, the project cannot take place as it is necessary to satisfy all planning and

permitting requirements before the planning authority or SEPA will allow operations to commence.

Where LFMR projects undertaken in other countries have included material recovery, this has most

commonly been for soil and metal recovery. The soil fraction of landfilled waste is generally very high,

typically around fifty percent, and is easy to separate. It is concluded that the best application of soils


from LFMR in Scotland is considered to be for use as daily cover in landfills. Metals (ferrous and

aluminium) are generally present at low quantities, in the case of the ‘typical’ non-hazardous landfill,

but they are relatively easy to separate out and have high value. The market for recovered metals is

strong.

With reference to metal recovery, landfill mining papers reviewed focused on recovery of ferrous

metals and aluminium. Other metals, including precious metals and rare earth metals, rarely featured

in the literature reviewed and only in a ‘maybe oneday’ perspective. The authors found no examples

of LFMR projects undertaken for the recovery of precious and rare earth metals and no papers

specifically discussing the viability of recovery of such materials.Whilst these metals are present in

some landfills, possibly at relatively high content in comparison to their concentration in their

respective ores, they will be present in a range of different applications, typically in WEEE and in some

industrial wastes. Recovery of precious and rare earth metals would give rise to significantly greater

technical complexity than for the types of LFMR operations discussed in this report.

Recovery of plastics for recycling is considered to be limited by high processing costs, poor anticipated

quality and lack of markets. It is considered that inclusion within RDF is the best route for this

material. If put back in the landfill, it occupies a lot of voidspace for its weight owing to its low

density.

Considering LFMR, at a national strategic level or on a one site basis, is very complex. The

permutations and combinations of drivers, waste type, quality and age, geometory of landfill, landfill

engineering, site setting, materials to be separated, technologies and local markets are very high. At

the outset of this study, the authors considered the information gained in the study might be best

presented in a matrix format, to readily inform those making decisions, such as landfill operators, local

authorities, ZWS, and the Scottish Government policy makers’. In undertaking this study, it has

become apparent that a matrix would need to accommodate too high a range of permutations and

combinations to be user friendly. In particular, the driver or particulars for a given region or landfill

type may give rise to variable weighting of the importance of some considerations.

Most LFMR projects undertaken worldwide have focussed on landfills that contain a mix of MSW,

commercual and industrial wastes. Similarly, it is concluded that the group of landfills, in Scotland,

considered most likely to contain candidates for LFMR are non-hazardous landfills, most of which

commonly contain all these wastes. According to 2010 SEPA data, these comprise:

48 operational landfills

2 landfills that were being restored in 2010

168 closed landfills still subject to regulation

An unknown number of closed landfills that have surrendered their licences. However, these are

not considered in this study owing to a lack of readily available data.

This study has concluded that LFMR involving onsite energy recovery at non-hazardous landfills could

potentially be economically viable, in particular at Scotland’s larger landfills. The ‘typical’ Scottish non-

hazardous landfill discussed in this study contains 1.3m tonnes of waste. This is based on 2010 SEPA

information for the total capacity of the 48 operational non-hazardous landfills in Scotland. The figure

is a median value calculated by excluding the two largest landfills in Scotland, namely Greengairs

Landfill in North Lanarkshire (35m tonnes) and Dunbar Landfill in East Lothian (13,6m tonnes). The

maximum total capacity of the remaining 46 landfills is 8.35m tonnes and the mean is 2.1m tonnes.

As these are operational landfills, some of this capacity is yet to be filled. In addition, this study has

ascertained that wastes over 25 years old are the most likely to be subject to a LFMR operation.

Therefore, the greatest number of landfills of potential interest are likely to be closed rather than

operational. There is no readily available data on the tonnage in Scotland’s closed landfills. However,

taking the size of Scotland’s operational landfills as an indication of size, and the number of closed


non-hazardous landfills, it is evident that Scotland is likely to contain landfills of sufficient size and age

to be potential candidates for a LFMR project involving onsite energy recovery.

Given the conclusions reached on the landfills likely to be candidates for LFMR and their age, in many

instances where LFMR could be considered the aerobic landfill concept will not be required to speed-

up the degredation process and minimise emissions of methane. The feasibility assessment in this

report has not considered the aerobic landfill concept. However, it is possible that in some situations

the use of the aerobic landfill concept may have merit, namely:

Where there are wastes worthy of mining although relatively high landfill gas levels would

otherwise preclude mining on the basis of explosion and odour risk. Where landfill gas can be

collected and utilised this approach would, however, have to be assessed in terms of cost and

benefit against collection of landfill gas and utilisation. Ultimately, the aerobic landfill concept only

brings forward the date of landfill mining, it does not alter what can or cannot be mined.

Where gas collection and utilisation is not practicable due to low gas levels or where gas levels

have declined to a level below which gas can be collected and utilised or flared, but where levels

are too high to allow LFMR.

Where gassing waste is to be excavated anyway, e.g. to make way for development or liner repair.

Although not necessarily related to LFMR, the aerobic landfill approach could be of interest in

minimising Scotland’s greenhouse gas emissions from landfills that are generating gas at levels that

do not allow collection and utilisation or flaring, or where collection and utilisation is otherwise

unfeasable. Besides older landfills, this could also apply to landfills experiencing ongoing reductions in

the receipt of biodegradable waste. Once there is insufficient gas to collect for utilisation or flaring, or

where levels are not sufficient to allow collection, there remains a significant period in which relatively

low levels of methane containing landfill gas is generated and simply lost to atmosphere. In addition

to reduction in the global warming potential of the landfill, additional benefits could include:

Bringing forward the return of the land to beneficial use.

Bringing forward the surrender of the landfill licence/permit.

Possibly mitigating local environmental impacts/risks from gas and leachate generation.

It is concluded that a LFMR project in Scotland is potentially feasible, given an optimum set of

conditions. However, the economic assessment undertaken in this study has been undertaken for a

hypothetical set of circumstances and with many assumptions. To undertake a detailed feasibility and

viability study for a specific landfill would require site specific data, a more sophisticated economic

assessment and more time and resource than has been applied to this high level scoping study.

Although potentially feasible, a project will only be viable if the landfill operator has the will to pursue

the project and has the ability to undertake it, or there is a third party willing to undertake it.

2.5 Recommendations

This study has been undertaken as a high level scoping study to inform ZWS and SG, whom want to

investigate whether or not LFMR is feasible and viable in Scotland. The study has not considered any

site specific data for any particular landfill. Instead, the focus has been to take an overview of a wide

range of issues that could potentially apply to LFMR across Scotland, as well as provide an insight into

what is involved in undertaking a LFMR project.

It is recommended that this study is shared with interested parties. As well as regulators and policy

makers, this should include landfill operators and companies that may be interested in being involved

in a LFMR project in Scotland. In addition to being a necessary step, if ZWS and the SG wish to


further investigate the undertaking of LFMR in Scotland, the insight and opinions of such stakeholders

will undoubtedly add to the understanding of the feasibility and viability of LFMR in Scotland.

If ZWS, the SG, or any other stakeholder is interested in pursuing the possibility of LFMR in Scotland,

it will be necessary to undertake a screening exercise to identify suitable landfills, and then to

undertake a detailed feasibility and viability study for a specific landfill. The screening exercise would

require access to a greater level of data than reviewed for this scoping study. Following the screening

exercise, it would of course be necessary to first establish operator interest. A screening exercise may

not be necessary if a landfill operator comes forward with a suitable landfill and a keen desire to

establish feasibility and viability of LFMR for that specific site.




LFMR project economics. The economic assessment presented in this study has not considered

incentives/credits for avoidance of fugitive emissions of landfill gas. It is, however, recommended that

consideration is given to this matter, in particular in relation to any possible future detailed site

specific feasibility assessment, as well as at a national policy level. In particular, consideration should

be given to whether a LFMR project in Scotland could qualify for Emission Reduction Units (ERUs)

under the Joint Implementation (JI) mechanism.

Whilst detailed composition analysis would be required in the development of a specific LFMR project

on a specific landfill, there would be merit in better understanding the waste in Scotlands landfills at a

higher level. The authors found no reference to the undertaking of composition analysis on landfilled

waste in Scotland. Understanding the compostion of landfilled waste in Scotland will better inform

assessment of LFMR feasibility. This would require trial pitting and sorting and analysis on landfilled

waste of known age and waste type. Whilst it would be prefereable to consider a high number of

landfills and undertake a high degree of sampling, such an exercise would not be straight forward.

Complications and expense would stem from health and safety considerations, environmental

considerations and subsequent repair of any damaged capping. It may be preferable to excavate one

or two trial pits on a number of landfills, instead of a greater number of trial pits on a lower number of

landfills.

In undertaking a landfilled waste composition exercise it would be useful to undertake detailed

analysis of specific wastes, e.g. in addition to having a category for small WEEE, that small WEEE

could be further broken down into type and material content. In-turn, this could inform a study into

the feasibility of the recovery of certain high value metals which, if not feasible now, might be feasible

in a future of increased resource scarcity.

It is evident that on-site energy recovery is a strong factor influencing financial viability of LFMR.

Whilst financial viability is currently borderline at best, it would be useful to undertake an assessment

of energy market trend to ascertain whether at some point in the future it is likely that energy from

landfilled waste (EfLFW) will be viable in its own right.

Finally, this study has highlighted the importance of understanding the waste present in a landfill to

LFMR and how this understanding is generally poor for historically landfilled waste. It is recommended

that consideration is given to methods of improving this situation going forward, e.g. what measures

can be taken to ensure operators record which wastes are placed where in a landfill and when.

Further to informing future potential LFMR, this will also assist those undertaking detailed modelling of

landfill gas and leachate and the undertaking of environmental risk assessments.


3 Feasibility and Evaluation of Oil Shale Bing Resource Reclamation

3.1 Overview

The bings located in West Lothian are post-industrial spoil heaps, the result of retorting mineral oil

from deep-mined carboniferous shale beds at a time when Scotland was the major oil producing

nation in the world. The bings seen across the West Lothian landscape are comprised of the waste

materials resulting from this process. The trade in crude oil and paraffin lead to the establishment of

several towns in the West Lothian area. The bings are now seen as a potential source of aggregate

replacement material, which can be used for construction purposes such as road bases and

foundations. The bings are also highly valued by local communities and historians. They are

considered an important landscape feature both as visual amenities and for the role they play in

reminding communities of their historical mining heritage. They are also seen as valuable for the

unique habitat which they provide, and for their use as a public open space.

At the end of the oil production era in Scotland, there were initially 27 bings in West Lothian as of the

end of 1963. There are now 19 bings remaining, which cover a total area of around 330ha.

A number of the West Lothian bings have been either restored or partially extracted already.

Restoration works in the past have historically been earth-moving exercises, changing the overall

shape of the bings to be rounder and theoretically more visibly attractive, and covering them with

topsoil, seeds and fertilisers. Extraction activities have been undertaken at other bings for the

purposes of the utilisation of the aggregate materials for construction purposes.

3.2 Evaluation of issues

3.2.1 Technical issues

Oil shale bings, as opposed to coal mining spoil heaps, have a greater physical stability. Therefore

there is less risk of collapse or landslides during excavation. This stability comes from the heating

process during shale oil extraction, whereby the oil shale is heated to enable separation of the shale

oil and the remaining bings are subsequently more chemically stable, absorb less water and contain

limited ‘fines’ materials. Recovering material from oil-shale bings is technically straightforward, and

will involve conventional excavating plant and equipment such as excavators, bulldozers and trucks.

Historically, material from oil shale bings has been used as a fill and subbase. WRAP, as part of the

AggRegain project, published a Material Information sheet (WRAP, 2011) which outlines the following

uses for bings material.

‘Based upon the Specification for Highway Works [MCHW Volume 1] and the Design Manual for Roads

and Bridges [HD 35/04], spent oil shale can be recycled into:

Hydraulically bound mixtures (HBM) for sub-base and base – spent oil shale is suitable for use in

HBS assuming it meets the appropriate material and grading requirements.

Unbound mixtures for sub-base – spent oil shale is suitable for use in sub-base assuming it meets

the appropriate material and grading requirements.

Capping – may contain spent oil shale.

Embankments and Fill – spent oil shale is generally suitable for embankment and fill applications.


The technical feasibility of recovering and using aggregate-type material from bings is well

established. Spent oil shale was used extensively and successfully in Scottish construction during the

1960s and early 1970s, but largely fell from use until the mid-1990s. The particle size distribution of

spent oil-shale means that it is particularly suitable for use as a granular subbase. Successful

applications of oil-shale bing material in the past has included general granular fill and unbound sub-

base on the M8, M9 and M90 motorways.

One of the more recent examples of the use of oil-shale bing material was in the upgrading of the

M8/M9 interchange in the early 1990’s. The junction was redesigned in order to allow through-traffic

to avoid a busy roundabout. This involved the excavation of an underpass below the roundabout.

Whilst the project requirements for fill material was limited, the nature of the excavations and limited

space on site meant that recycling the excavated material was not practical. The quality of the

excavated material was also not of sufficient quality to be recycled on-site. However, the site was in

close proximity to the West Lothian oil-shale bings, with the nearest bing (known as ‘Green Bing’) only

four miles from the site. In this instance, the use of locally available oil-shale as an aggregate was

therefore preferable to the recycling of the excavated material or the import of virgin aggregate.

Approximately 15,000m3 of oil-shale bing material was used as fill in the entry and exit ramps of the

M8 and M9 junctions at the interchange. The oil-shale material meets the requirements of the

Specification for Highway Works (SHW) 600 series. The SHW describes which recycled and secondary

aggregate materials are acceptable for use in earthworks, and specifies the tests which need to be

carried out.

There is no performance data relating to the use of oil-shale bing material in the M8/M9 interchange

project. However, the work was completed in accordance with the SHW specification and since the

new junction opened in 1997 there have been no adverse issues related to the spent oil-shale

earthworks.

During excavations of compacted oil-shale, it has been observed that the material undergoes a small

amount of crushing when compacted. This means that there is less void space between the particles,

which in turn leads to a higher strength, less permeable material when compared to other aggregate

fill materials, including many primary and virgin aggregate materials.

3.2.2 Economic issues

In the West Lothian Local Biodiversity Action Plan report on Oil Shale Bings (Harvie, 2005a), the

economic value in the bing materials as construction materials is noted, but also says that

‘…paradoxically, this monetary value has also protected them from demolition and landscaping at the

end of the twentieth century when reclamation and restoration of mine waste was fashionable.’

However, the economic value of the bings is now seen as a threat to their security, especially in light

of some of the bings being privately owned.

Research into the current market and costs of virgin and recycled aggregates in the West Lothian area

has been undertaken in order to determine the potential value of the bing material. Using the Zero

Waste Scotland, Aggregates Quality Protocol Supplier Directory (http://www.zwsaggsuppliers.org.uk),

suppliers in or neighbouring the West Lothian area were contacted. This directory is based upon the

businesses that have been proved to comply with the WRAP Aggregates Quality Protocol.

The range of estimated prices for virgin or secondary aggregate was as follows:

Virgin aggregate: £11 – £12 per tonne

Secondary aggregate: £6 - £12.50 per tonne

Transport: £5 per tonne (up to 10 mile radius)


Based on these price estimates, it is clear that aggregates recovered from oil-shale bings would have

significant value, and could compete with other aggregate materials in terms of cost. Whilst the exact

quantities of oil-shale bing material remaining is not known, some estimates have been in the region

of 100 million tonnes.

Oil-shale aggregate is a cost-effective material to extract, as with many aggregate materials, the

transportation costs are the barrier to their use elsewhere and it is likely to be uneconomical to

transport bing material significant distances. Most of the organisations listed on the supplier directory

will deliver up to a 30 mile radius.

The demand for oil-shale from bings has been cyclical in the past, with high levels of demand being

associated with major construction projects.

In terms of current demand for aggregates (either virgin or recycled) within the West Lothian area,

the biggest single construction project currently in progress is the Forth Replacement Crossing.

Construction work began in September 2011 and is due to completed by 2016. Aggregates suppliers

to the project have been announced as Tarmac (Ravelrig Quarry in West Lothian) and Aggregate

Industries (Glasgow Depot). The environmental statement for the Forth Replacement Crossing work

(Transport Scotland, 2009) states that in addition to imported aggregates, the blasted rock gathered

during excavations at the site will be utilised as aggregates during the construction (App A4.1 section

5.9.4).

3.2.3 Environmental issues

The original process of producing shale oil had significant environmental impacts on the West Lothian

area. The production of a barrel of shale oil can result in up to 1.5 tonnes of spent shale, which is

evident in the large bings now remaining across the region. The disruption to land was perhaps the

most significant impact of the oil shale industry, but the legacy of the bings may also give rise to

further environmental impacts. The weathering of the oil shale waste may result in these materials

leaching into local water courses. It is thought that the impact on water quality by oil shale wastes is

similar to that of coal mining wastes, but a 2005 European Parliament study on the EU oil shale

industry recommended that further research is carried out into the environmental impact of oil shale

wastes on the environment and water environment.

Local studies have confirmed that bing water run-off has resulted in significantly elevated levels of

iron in water courses. One paper (Haunch et al, 2011) outlines how 300 years of both coal and oil

shale mining activity continues to impact water quality in the Almond River catchment area. Oil shale

wastes in Scotland have been identified as containing significant quantities of iron (Fe2O3) and sulphur

(SO3). Scottish shale oil was produced almost entirely within this river catchment area. However the

study determined that it was predominantly coal mining waste which contributed to the impact on

water quality, with the contribution of iron and sulphate loading from oil shale waste more difficult to

determine.

During the working of a bing, any neighbouring residents and communities are likely to be subjected

to adverse environmental consequences. These will include dust, mud, and traffic noise. In 2009, the

City of Edinburgh Council undertook a review of conditions of an existing minerals permission at the

Niddry Castle bing. The Niddry Castle bing lies within West Lothian Council, but is near to and visible

from areas of the City and County of Edinburgh. The review was undertaken as a requirement of the

Environment Act 1995 which requires that any mineral permissions are reviewed every 15 years to

ensure that modern operational and environmental standards are maintained over the life of mineral

planning permissions. The Niddry Castle Bing has been an operational minerals site for at least 15

years (in 2009). The review established that any adverse environmental impacts from the working of

the bing are linked to noise, dust or air quality but are likely to be limited to the area immediately


surrounding the operations. The review also outlines the set of planning conditions in place to limit

environmental impacts. These include measures aimed at ensuring lorries are suitably sheeted, and

wheel cleaning facilities are in place. Hours of operation of the site are also restricted to minimise the

impact of noise.

3.2.4 Regulatory issues

Subject to the application of end of waste criteria, the processing and reuse of bing material may be

subject to waste management licencing. Ricardo-AEA consider that the material in the bings meets the

definition of waste as given in the Waste Framework Directive. Ricardo-AEA consider that its reuse as

an aggregate would either require confirmation that it is no longer considered a waste, or require the

application of waste management licensing provisions. On a case by case basis, this will require prior

discussion with SEPA.

The ‘quality protocol for the production of aggregates from inert waste in Scotland’ (WRAP, 2004)

provides information on determining end of waste status. In using this protocol, it would first be

necessary to establish if the bing material meets the criteria for ‘inert waste’ given in appendix C of

the protocol. The waste does not neatly align with the list of wastes considered ‘inert’ in appendix C of

the document and it is possible that it may not be considered ‘inert’ given references reviewed which

suggest both iron and sulphate can potentially leach from the bings (see Section 3.3.3 above), with

resultant potential impact on water quality.

The main regulatory issues relating to the excavation of materials from the oil-shale bings are

associated with planning. In 1998, West Lothian Council published ‘A development control policy to

control the extraction of oil shale bings in West Lothian Scottish’ (West Lothian Council, 1998) as a

Supplementary Planning Guidance document. The policy outlines the Councils’s approach to

encouraging or resisting the excavation of bings. It also documents good practice and considerations

for future bing developers and restoration projects to limit environmental consequences.

The council’s policy towards extraction of materials is based on a preference to work already partially

worked bings and to resist extraction of many of the intact bings. Their past experience of extraction

from the oil-shale bings has led to the division of bings into four categories:

1 Category 1: Bings where extraction is encouraged. Bings in this category include some with

existing planning permission and some without planning permission.

2 Category 2: Intact bings where extraction is resisted. This includes bings such as Five

Sisters, which is a particularly large bing and striking landscape feature. The council would

encourage the development of recreation and tourist facilities here. The council has also identified

other bings in this area for which it would support scheduling as an ancient monument.

3 Category 3: Restored bings where extraction is resisted. The council have identified bings

for which there is no potential for further extraction, and which have been restored to either

recreational or industrial land. However, some of these may be considered for extraction should all

other resources be worked.

4 Category 4: Bings which have been abandoned or where resources are exhausted.

Restoration encouraged. These include bings which have been abandoned by the operators, and

some which have only been partially restored.

Planning applications for extraction from bings will be subject to the following conditions set by West

Lothian Council:

Planning permission will be subject to conditions specifying a limited working area within the bing,

including areas for disposal of clinker and other unsuitable materials.

Extraction should proceed in level steps avoiding jagged edges.


Bing operators will be expected to install a tarmac surfaced access road and wheel wash.

Detailed conditions will be included in planning consents with respect to site restoration.

The Council may also require a restoration bond before granting planning permission.

3.2.5 Sociological issues

The West Lothian bings are considered by many to have significant social and historic importance.

Some bings are already scheduled as historic industrial monuments. They also have an educational

value, in terms of the industrial history of the local area. They are considered by many to be an

important landscape feature, both for visual amenity value and for the part they play in reminding the

community of its historic mining heritage.

The bings are also used for recreational purposes, especially those that have been restored for this

purpose. Many bings are situated in close proximity to residential areas, and some are used on a daily

basis by dog walkers and joggers, and provide important open spaces for communities in the area.

Some bings have been restored specifically with recreation in mind, including one bing that is now a

Scottish Wildlife Trust nature reserve. Other recreational users of the bings include botanists and

cyclists.

The sociological impact of extracting materials from the bings will impact communities in two different

ways. Firstly, extraction will change the landscape, which for many has become an integral part of the

identify of West Lothian communities. Extracting material from the bings can also add to their derelict

appearance, with some working leaving unattractive profiles. Secondly, the environmental impact of

extraction may have an adverse impact on local communities, as outlined in Section 3.2.3. Whilst

measures can be put in place to minimise the impact of extraction activities, the review of activities at

the Niddry Castle bing revealed that local roads were often covered in dust, and residents had

complained of excessive noise. Local roads have been damaged, and other issues such as works

vehicles travelling at excessive speeds and the parking of heavy goods vehicles in the village centre

were reported as having an adverse impact on village amenities. These impacts, however, could be

encounterred with any mining activity, including the quarrying of virgin aggregates, and are not

unique to the extraction of materials from bings.

3.2.6 Ecological value

The oil shale bings of West Lothian have been of significant academic interest to ecologists at the

University of Edinburgh since the early 1970s and have been the subject of undergraduate and

masters’ projects and a doctorate thesis (Russell, 1971; Martin, 1992; Maka, 1995; Harvie, 2005b).

The West Lothian Biodiversity Action Plan (LBAP) for oil shale bings (Harvie, 2005a) regards the 19

bings that survive as unique in Britain and north-west Europe. Those bings that are of greatest

ecological importance have remained largely unmanaged since shale extraction ceased (1920–1962),

and are examples of primary succession, a process resulting from natural colonisation usually only

associated with sand dunes, glaciers and volcanoes. Their vegetation has been determined primarily

by local seed sources and to a lesser degree by the rare and chance arrival of species from further

afield (Dickson, 1990; Harvie, 2005a, 2005b, 2012; Harvie & Russell, 2007; Harvie et al., 2003,).

Other bings have been re-landscaped and planted, mostly during the 1970s and 1980s.

Increasingly intensive agriculture and urban development means that the bings have become a refuge

for wildlife. Allowed to develop naturally, the bings’ varied substrates give rise to a wide range of

habitats, from almost bare ground to semi-natural grassland, heather, scrub and birch woodland (Hall,

1957). Eight species (all lichens and mosses) with Nationally Scarce status in Great Britain are only

found in West Lothian on oil shale bings (Harvie, 2005a; Steven & Long, 1989). Sixteen of West

Lothian’s rarest plants are recorded on the bings (Smith et al., 2002). The bings are cited in the LBAP

as playing a major role in the success of 15 of the 45 West Lothian habitat indicator species: bird’s

foot trefoil, brown hare, bullfinch, grey partridge, kestrel, linnet, orange tip butterfly, red grouse,


skylark, song thrush, spotted flycatcher, swallow, wild hyacinth (bluebell), yellowhammer, and yellow

rattle (Harvie, 2005a). Some bings are also home to badgers, which are protected by the Protection of

Badgers Act 19921.

The bings contribute to wider habitat networks, defined by species’ abilities to disperse across the

landscape, which can be viewed using a web-based tool, currently being trialled by Scottish Natural

Heritage (SNH) for the Central Belt of Scotland, at

http://mapgateway.snh.gov.uk/maps/usertool_editor.html (see Figure 3.1).

1 http://www.legislation.gov.uk/ukpga/1992/51/contents

http://mapgateway.snh.gov.uk/maps/usertool_editor.html


Figure 3.1 Habitat networks for generalist species

a) Heathland (purple) b) Woodland (green) c) Grassland (orange)

The bings may act as functional links between wildlife sites in their vicinity, including a number of

Sites of Special Scientific Interest (SSSIs), Easter Inch Moss and Seafield Local Nature Reserve (LNR),

and numerous Scottish Wildlife Trust (SWT) reserves and Woodland Trust (WT) sites (see Figure 3.2).

Figure 3.2 Wildlife sites in the vicinity of the 19 surviving bings

SSSIs (pink polygons) LNR (mauve polygon)

SWT reserves (green dots) WT sites (pale pink polygons)


3.2.6.1 Biodiversity Action Plan target and actions

Only four of the 19 surviving bings have formal protected status, three are Scheduled Ancient

Monuments (SAMs) and one is part of the LNR already mentioned, see Table 3.1. An LBAP target is

to:

“Secure formal protection for all of the remaining oil-shale bings through the local plan, as examples

of primary succession processes and for their contribution to the biodiversity of West Lothian, and as

industrial heritage sites because of their historical significance” (Harvie, 2005a).

The LBAP advocates that the best management of oil shale bings is no management. Low nutrient

availability, grazing, trampling, and off-road biking have all helped to increase plant diversity.

Restoration and management of spoil waste are viewed as unnecessary and undesirable from a

biodiversity perspective. The LBAP reports that restoration policies have led to species-poor, visually

boring sites, except where semi-natural habitats have been deliberately established and steep slopes

retained. A proposed action for the bing habitat in the LBAP is to:

“Discourage restoration programmes on all 19 bing sites even after extraction. To maintain and

enhance the bing habitat management should be kept to a minimum. Sites only require minor

regrading to remove overhangs and stabilise large blocks of clinker so that they are made safe. Retain

old elder trees whenever possible as they are a unique source of epiphytic lichen and moss diversity”

(Harvie, 2005a).

The LBAP proposes specific actions for each bing, only where required. Broadly speaking, these seek

to:

Protect and, where appropriate, manage existing habitats

Control non-native and invasive species

Use enrichment planting to make badly restored sites more attractive and interesting

Promote and manage public access.

3.2.6.2 Planning context

A development control policy to control the extraction of oil shale bings in West Lothian (West Lothian

Council, 1998) categorised the bings based on the need first to remove those that were already

partially worked and to restrict extraction from intact bings. It also noted that some restored bings

may have potential for further extraction once other sources are exhausted.

The LBAP (Harvie, 2005a) stated that recent changes to local conservation policy had ensured that

many remaining were safe from demolition, reshaping, reclamation and restoration, although a few

had been sold with a pre-designation allowing them to be removed for construction work and that

application could be made to excavate some others, as listed in Table 3.1.

Policy NWR4 and Policy NWR5 in successive West Lothian Local Plans (West Lothian Council, 2005;

2008) are of relevance to mining and reclamation of bings and include clauses that relate to ecological

issues.

Policy NWR4 states that proposals for mineral extraction are more likely to be given favourable

consideration where areas of derelict or contaminated land would be rehabilitated. In this context,

although oil-shale waste is generally non-toxic and alkaline (Harvie, 2005a), it may be notable that

two bings (Table 3.1) have been documented as being sources of water run-off and minewater

rebound that have resulted in significantly elevated levels of iron in water courses, with ferruginous


inputs smothering habitats and reducing biodiversity (Johnston et al., 2008; McConnell, 2011).

However, Policy NWR4 also states that circumstances where mineral extraction is unlikely to be

acceptable include ecologically and geologically sensitive areas and that:

“Special Areas of Conservation, Special Protection Areas, National Nature Reserves, Sites of Special

Scientific Interest, Local Nature Reserves and other sites of local ecological, or earth science

importance will be protected from proposals which affect the integrity of the feature”.

Policy NWR5 states that proposals for mineral extraction are less likely to be given favourable

consideration in ecologically sensitive areas or where the long-term biodiversity value of the site would

be reduced by the development.

Table 3.1 The 19 surviving bings (Harvie, 2005a, 2005b; Johnston et al., 2008, McConnell, 2011)

Na

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Addiewell north NT002631 12ha 1932

Addiewell south NT005627 30ha 1932

Albyn NT085729 6ha 1925

Bridgend NT037758 12ha 1932

Clapperton NT079697 11ha 1925

Deans Bing NT015685 74ha 1946

Drumshoreland

north

NT075700 26ha 1925

Drumshoreland

south

NT078695 7ha 1925

Faucheldean NT085742 9ha 1925 SAM

Five Sisters

(Westwood)

NT009641 17ha 1962

SAM


Green Bing NT070710 9ha 1920

Greendykes

(north part)

NT087736 33ha 1925

SAM

Mid Breich NT009646 4ha 1915

Niddry NT097746 8ha 1961

Oakbank NT076664 13ha 1932

Philipstoun north NT057769 10ha 1932

Philipstoun south NT056765 27ha 1932

Seafield NT005667 12ha 1932 LNR

Stankards NT063711 10ha 1920

3.2.6.3 Impact assessment

There are no sites of European importance for nature conservation in the vicinity of any of the

surviving bings. As such, the requirements of the The Habitats Regulations2 are not a relevant

consideration.

Open-cast mining where the surface of the site exceeds 25 hectares is listed in Schedule 1 to the

Environmental Impact Assessment (EIA) Regulations3, as such mining and reclamation of bings that

meets this criterion will require an EIA (see Table 3.1). Mining and reclamation that covers a lesser

extent is addressed by Schedule 2 to the EIA Regulations and will require EIA if it is likely to have a

significant effect on the environment, by virtue of factors such as its size, nature or location.

Guidelines for ecological impact assessment (EcIA), as part of an EIA, produced by the Institute of

Ecology and Environmental Management (IEEM) advocate that an EcIA should include the following

stages:

1 Consultation to ensure the widest possible input to the definition of its scope, which should be

iterative throughout the EcIA process

2 Identification of the likely zone of influence during the project’s entire lifespan

3 Identification and evaluation of ecological resources and features likely to be affected

4 Identification of changes likely to affect valued ecological resources and features

5 Assessment of whether changes are likely to have a significant ecological impact on the integrity

of a site and/or conservation status of habitats or species within a given geographical area,

including cumulative impacts of a project in association with other developments in the vicinity

6 Refinement of the project to incorporate ecological enhancement measures, mitigation measures

to avoid or reduce negative impacts, and compensation measures for any residual significant

negative impacts

7 Assessment and definition of the significance of the refined project’s ecological impacts

2 The Conservation (Natural Habitats, &c.) Regulations 1994; The Conservation (Natural Habitats, &c.) Amendment (Scotland) Regulations 2004;

The Conservation (Natural Habitats, &c.) Amendment (Scotland) Regulations 2007; The Conservation (Natural Habitats, &c.) Amendment (No. 2) (Scotland) Regulations 2007. http://www.legislation.gov.uk/ 3 The Town and Country Planning (Environmental Impact Assessment) (Scotland) Regulations 2011. http://www.legislation.gov.uk/

http://www.snh.gov.uk/protecting-scotlands-nature/protected-areas/international-designations/natura-sites/habitats-regulations

http://www.legislation.gov.uk/ssi/2011/139/contents/made


8 Advice on the implications for decision-making of those ecological impacts deemed significant

9 Monitoring implementation and success of mitigation measures in relation to predicted ecological

outcomes.

More specifically, SNH has identified a number of questions that should be considered when a bing,

which is perceived to have natural heritage value, is scheduled for reclamation (McKenzie, undated;

Allan et al., 1997):

1 What features of a bing are of natural heritage value worthy of protection? Are they

unique/rare/common? If so:

2 Is it essential to retain the whole bing to protect the natural heritage interest?

3 Will earth moving operations and/or application of amendments, change the important habitat or

environmental features of the bing?

4 Can the natural heritage aspects of the existing bing be incorporated into the landscape design for

the reclaimed site?

5 Are there any opportunities to create natural heritage interest on a reclaimed bing, for example,

by creation of an artificial wetland habitat?

6 Are there any educational opportunities to use a site because of its industrial heritage or

habitat/nature conservation value?

SNH uses the questions to highlight that any bing reclamation proposals should ensure that the

distinctive and potentially unique natural heritage interest is adequately considered.

In practice, potential ecological concerns arising from any intent to mine and reclaim the bings will be:

Habitat and species loss associated with the sites themselves, particularly given:

The presence of Nationally Scarce species and habitat indicator species

The length of time species have had to colonise some sites (Table 3.1)

The fact that re-colonisation will be more difficult due to the increased intensity of land use

in the intervening matrix between bings and wildlife habitats

Fragmentation of habitat networks in the wider landscape. This may be assessed using the web-

based tool currently being trialled by SNH at

http://mapgateway.snh.gov.uk/maps/usertool_editor.html. As well as allowing users to view

existing habitat networks, it can be used to scenario plan reclamation options by drawing the

shape of resultant land parcels on screen, assigning a land use choice from a drop down list, and

then viewing the effects the changes have on the wider habitat network associated with a bings.

The tool is web-based, freely available and requires no specialist software or GIS expertise. A

guide to its use is available at: http://www.snh.gov.uk/docs/B1029694.pdf

Emissions to water that may also impact on other wildlife habitats of national or local importance

within a wider zone of influence, particularly SSSIs, Easter Inch Moss and Seafield LNR, SWT

reserves and WT sites

Ability to retain important habitat features

Ability to retain vestiges of the substrate as chaotic micro-topography for repeat colonisation

Ability to promote, accommodate, adapt or augment specific actions identified for each bing in the

LBAP (Harvie, 2005a), as part of extraction or post-extraction operations.

Any proposal for active restoration, including habitat and species translocation, which will not be

viewed as suitable mitigation (Harvie & Russell, 2007).

http://mapgateway.snh.gov.uk/maps/usertool_editor.html

http://www.snh.gov.uk/docs/B1029694.pdf


3.3 Conclusions

The recent extraction of material from oil-shale bings demonstrates that the recovery of material for

use in construction applications is both technically and economically feasible. The economic feasibility

does depend on distance between the bing and point of use, and it is unlikely that the bing material

would be used other than in areas in proximity to West Lothian. Whilst the aggregate material does

have some advantages in particular applications, it is generally used as low grade fill material, of

which there are numerous other sources, both virgin and secondary, in the wider area and the rest of

Scotland.

A review of the ecological issues associated with the bings has demonstrated the ecological

importance of the bings, due to the unique and diverse habitats that they provide. There are

undisputable ecological benefits as a result of leaving bings untouched.

The environmental impacts of extracting bing material will be localised, but could be significant for

local communities. Similarly, the sociological impacts of working or removing the bings will also impact

locally, on communities who have come to accept the bings as a permanent and important feature of

their local landscape.

West Lothian Council have already taken into consideration the National Planning Policy Guideline

NPPG 4: Land for Mineral Working, which suggests that local planning policies should provide for the

recycling of demolition and construction wastes (including oil-shale bings) wherever possible. In

recognition of the policy guideline, the council have categorised the bings to determine which type of

bing has the most potential for extraction of materials. Out of the 19 remaining bings, only four have

existing planning permission with extraction being encouraged. There are a further three at which

extraction may be encouraged, but which do not currently have planning permission. The remaining

bings are either restored, protected or have already been exhausted of materials. Therefore the actual

potential for extracting materials from the bings may be smaller than initially expected. The fact that

the council have stated that they will resist extraction proposals for bings which remain fully intact

suggest that the ecological and social importance of these sites has been recognised.

In conclusion, whilst there are some sources of aggregates which could readily and economically be

extracted from the bings, the ecological, environmental and sociological impacts on local communities

will be significant, and will need to be considered on a case by case basis.


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management of post-industrial sites. Aspects of Applied Biology, 82, 57-64.

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of Historic Mining Activities in the Almond River Catchment, Scotland. IMWA 2011.

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Lothians. Edinburgh University Press.

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http://www.dpea.scotland.gov.uk/Documents/qA297654/A3094556.pdf


Appendices

Appendix 1: Scotland’s licensed/permitted landfills (in use- 2010)

Appendix 2: Scotland’s licensed/permitted landfills (closed- 2010)

Appendix 3: Summary of selected SEPA data on Scotland’s landfills

Appendix 4: Worldwide historic and current LFMR projects and drivers

Appendix 5: Economic model


Appendix 1 – Scotland’s licensed/permitted landfills (in use-

2010)


Appendix 2 – Scotland’s licensed/permitted landfills (closed-

2010)


Appendix 3 - Summary of selected SEPA data on Scotland’s

landfills


Landfill

status

(2010)

Number

of

landfills

Landfill

classification Waste type Site Type Capacity

Date of permit/

licence issue4

Operational 72 23 (31.9%)

inert (incl. 4

inactive)

1 (1.4%)

hazardous

48 (66.7%)

non-

hazardous

(incl. 2

inactive)

Of the 48 non-

hazardous landfills, 16

contained cells for

asbestos waste

43 (65%) of the 66

active sites were

permitted to receive

household waste, of

which all but 1 was

also permitted to

receive commercial

waste and all but 7

was permitted to

receive industrial

waste as well.

39 (59.1%) of the

66 active sites

were just landfill,

the remainder had

other facilities

Of the 48 non-hazardous landfills:

Remaining landfill capacity is 63,977,097 tonnes

Overall total capacity is 143,071,473 tonnes

Minimum total capacity is 27,000 tonnes, maximum

is 35,000,000 tonnes, mean is 3,044,074 tonnes

and median is 1,500,000 tonnes.

Excluding the 2 largest landfills (Greengairs Landfill

in North Lanarkshire at 35,000,000 tonnes and

Dunbar Landfill in East Lothian at 13,601,000

tonnes), the maximum total capacity is 8,350,000

tonnes, the mean is 2,099,344 tonnes and the

median is 1,320,000 tonnes.

The data indicates a probability that 6 to 8 landfills

are nearing being full (likely to be the case by

2015)

All between 2004 and

2010, reflecting the

introduction of the

PPC permitting

regime. Most of the

landfills will have

been in operation

prior to this.

Licence or

Permit in

force and in

restoration

10 8 (80%)

inert

2 (20%)

non-

hazardous

1 non-haz site was

licensed to receive

household,

commercial, industrial

and asbestos waste

1 non-haz site was

licensed to receive

household,

commercial and

industrial waste

Both non-haz

landfills are landfill

only facilities

One of the non-haz landfills had a remaining

voidspace of 2,000,000 tonnes

The non-haz landfills:

1 in 1998

1 in 1995

All sites are regulated

under the waste

management

licencing regime

Licence or

Permit in

force and

175 Not stated 5 (2.9%) inert only

16 (9.1%) household

only

159 (90.9%) were

just landfill, the

remainder had

Of the 74 landfills receiving household waste, 4 did

not have a restriction on the rate of waste receipt, 2

had a daily waste limit and 68 had an annual limit. Of

9 were either not

known or entered

in error

4 The date of licence/permit issue is an indicative but not absolute indication of landfill age. Many licences and permits are varied or replaced with issue of new reference numbers and so the landfill may be older than the

dates listed.


Landfill

status

(2010)

Number

of

landfills

Landfill


Date of permit/

licence issue4

closed 26 (14.9%)

commercial only

46 (26.3%) industrial

only

1 (0.6%) special

waste only

1 (0.6%) unknown

81 (46.3%) with more

than 1 waste type

74 (42.3%) took

household waste (16

only HH waste)

12 of the landfills

taking household

waste also took inert

waste

7 of the landfills

taking household

waste also took

asbestos waste

7 of the landfills

taking household

waste also took

special waste

54 (73.0%) of the

landfills taking

household waste also

took industrial and

commercial waste

other facilities these annual limits:

1 was 1,000,000 tonnes

were between 500,000 and 600,000 tonnes

6 were between 100,000 and 300,000 tonnes




2 were less than 1,000 tonnes

12 were issued

between 2000 and

2007

124 were issued

between 1990 and

1999

20 were issued

between 1980 and

1989

10 were issued in

either 1978 or

1979

Of the 74 landfills

that received

household waste:

6 were issued

between 2000 and

2005

54 were issued

between 1990 and

1999

11 were issued

between 1980 and

1989

were issued in

either 1978 or

1979

Licence or

Permit not in

100 Not stated but

review of

Not stated Not stated Not stated Tend to have older

permit issue dates, or


Landfill

status

(2010)

Number

of

landfills

Landfill


Date of permit/

licence issue4

force and

closed5

operator names

suggests high

prevalence of

inert landfill

incorrect dates, than

other closed sites

5 These landfills feature in the SEPA data associated with ‘landfill sites and capacity report for Scotland 2010’ but not ‘waste sites and capacity report for Scotland 2010’. It is suspected that these 100 landfills refer to

landfills previously regulated which have now surrendered their licences, although this is not categorically stated in the SEPA data. These sites tend to have older permit issue dates, or incorrect dates, than the other sites and perusal of the operator names suggest many of these sites are probably inert landfills.


Appendix 4 - Worldwide historic and current LFMR projects

and drivers


Sites (UK) Project drivers Comments

Packington Landfill,

Birmingham, UK

In order to enable the landfill lining to be

upgraded.

Whinney Hill,

Lancashire

In order to fulfill landfill directive obligations

(restructuring and re-lining the site). To

allow for a free-standing bund to be

installed.

Jameson Road,

Lancashire

In order to fulfill landfill directive obligations

(restructuring and re-lining the site). To

allow for a free-standing bund to be

installed.

Old dockyard tip at

Chatham dockyard

estate, UK To allow housing development

No sorting of waste other than

removing obvious hazardous

wastes. Waste removed by train

to Bedford brick pits. Undertaken

in the 1980’s.

Two council landfills,

Kent, UK

Two Domestic waste landfills excavated and

moved to allow construction of the channel

tunnel rail link.

Complete relocation of pre 1974

waste to a specially constructed

engineered landfill (Marley Pit).

No sorting of waste other than

removing obvious hazardous

wastes. Undertaken in year

2000.

Sussex, UK

To make way for extension to the

recreational Bluebell railway in Sussex.

Trial excavation only. No sorting

of waste other than removing

obvious hazardous wastes.

Sites (Europe) Project drivers Comments

Sondermulldeponie

Kolliken, Switzerland

To avoid potential groundwater pollution

risks. Hazardous waste landfill

Goettingen landfill,

Deidrode, Germany Not specified.

Burghot, Germany Not specified.

Believed to be the first of its kind

in Europe.

Schoneiche, Germany Not specified.

Dresden, Germany Not specified.



Sengenbuhl,

Germany Not specified.

Basslitz, Germany Not specified.

Dobeln-Hohenlauuft,

Germany Not specified.

Arnhem, Netherlands To develop the site as an industrial area.

Born, Netherlands To develop the site as an industrial area.

Appledoorn,

Netherlands

To avoid polluting the environment

surrounding the landfill.

Heiloo, Netherlands In order to create more landfill capacity.

Zeeasterweg landfill,

Lelystad, Netherlands Not specified.

Smwell-Well System for reducing

odours prior to excavation.

Remo landfill (Remo

Milieubeheer NV),

Houthalen-

Hechteren, Belgium

For the recycling of materials and capture of

residues to be processed through APP's

patented Gasplasma technology (feeding

into the national electricity grid and vitrified

recyclate in the form of Plasmarok). For the

reclamation of the site for community

recreation. Not commenced yet

Sardinia, Italy For the recovery of landfill capacity.

Masalycke landfill,

Sweden

This was a research investigation to

evaluate the rate of degradation of buried

waste and research recycling and energy

recovery potential of the materials

excavated. Research investigation

Gladsax landfill,

Sweden



waste and research recycling and energy

recovery potential of the materials

excavated. Research investigation

Filborna landfill,

Sweden Not specified. Pilot test.

Filborna, Sweden Not specified. This was a pilot test carried out

in 1994 on a 10 year old section



of the landfill.

Strangnas, Sweden

For the recovery of landfill capacity and the

recovery of materials.

Landskrona, Sweden Not specified. Pilot test.

Laguja Landfill,

Estonia

For the rehabilitation of a ponded area and

in order to facilitate landfill capping.

Vassiliko Cement,

Cyprus Not specified.

Sites (North

America) Project drivers Comments

McDougal, Ontario,

Canada To mitigate groundwater contamination.

Naples Landfill,

Collier County

Florida, USA

Due to the identifications of a threat to

groundwater locally and the high cost

required to comply with the State's capping

regulations (impermeable cap on

completion).

Now being undertaken for the

removal of the soil fraction only

as quality of recyclates was too

poor.

Martone Landfill,

Barre,

Massachusetts, USA

In order to expand existing landfill capacity

with new cells to be lined for future filling

(landfill upgrade).

High leachate head found to

have reduced degradation of

waste.

Bethlehem, New

Hampshire, USA Pollution prevention.

New owners took over the site.

Regulators required them to

move 160 tonnes of material to

new lined cells.

Bethleham,

Pennsylvania, USA

In order to upgrade the site via the removal

of old waste (from 1942 onwards), re-grade

the slopes and put in a new liner. Allowing

future landfilling. Also, for the purposes of

avoiding groundwater contamination.


Sites (North


Edinburgh, New York,

USA

In 1988, the New York State Energy

Research and Development Authority put

out a request for an appropriate landfill

mining project site.

The objectives of NYSERDA in undertaking

the Edinburgh project were as follows:

- to determine the equipment needs and

develop optimal procedures for excavation,

- to understand the extent of separation,

handling, and storage of landfilled materials

- to determine appropriate uses for the

reclaimed material

- to identify available markets for the

materials

- to develop required processing needs for

the reclaimed materials

- to develop recommendations regarding

health and safety requirements

- to conduct contingency planning for

future landfill reclamation projects in New

York.

This work was based upon the

success of the Collier County

landfill mining work.

Frey Farm landfill,

Manor Township,

Lancaster,

Pennsylvania, USA

In order to supply more feed for a three-

train massburn facility with a design

capacity of 1,100t/d.

Mining ceased once the

neighbouring capacity for the

mass burn facility was reached.

Town of Thompson,

Connecticut, USA

In order to stop the landfill from having to

close (by it's planned due date), to

recapture landfill volume.

This was considered a temporary

activity while a new landfill

solution for the area was

confirmed.

Horicon, New York

State, USA Not specified.

Chester, New York,

USA Not specified.

Coloni, New York,

USA Not specified.

Sandtown, Delaware,

USA Not specified.


Sites (North


Hague, New York,

USA

To remove the old waste from the landfill

mitigate any future monitoring and aftercare

risks.

Newbury,

Massachusetts, USA

To reclaim the 9 acre footprint. To create a

new lined cell to avoid the potential for

groundwater contamination.

Halifax, Vermont,

USA

The landfill was deemed not to have been

engineered correctly (the sides were too

steep). To remove the waste, re-engineer

the slope sides and re-landfill the waste.

Nashville, Tennessee,

USA

In order to alleviate contamination concerns

and to recycle soil and ash as road base.

Perdido landfill,

Escambia County,

Florida, USA

To create voidspace and allow the State to

decide whether or not it would continue

landfill mining on the remainder of the

unlined sections of the landfill. To define

economic feasibility and operational

considerations that need to be made.

Substantial State funding

received for this demonstration

project.

Sites (Asia) Project drivers Comments

City of Tel Aviv,

Israel

Landfill mining was first reported in Tel Aviv,

Israel. The objective was to excavate waste

to obtain 'soil amendment' materials (with a

concentration of NPK fertilisers of 1.4%).

This soil amendment was used to cultivate

Citrus groves in the area. Materials were

not used in other agricultural activities due

to the large amount of broken glass present.

First landfill mining project

undertaken.

Metro Manila

Commission, Island

of Balut, Tondo,

Philipines To upgrade the existing landfill.

Never went ahead due to a

shortage of funding.

Non Khaem Landfill,

Bangkok, Thailand Not specified.

Non Khaem, Thailand Not specified.


Sites (Asia) Project drivers Comments

Nanjido Landfill,

Seoul, Korea

In order to alleviate the environmental

concerns and create a recreation area on

the site.

Deonar, India

This was a pilot test to enable the recovery

of decomposed waste as compost. Pilot test

Ajmer Project,

Rajastan, India

In order to capture an alternative fuel

source.

Kodungaiyur, India



waste and research energy recovery

potential of the materials excavated. Research project

Perungudi, India



waste and research energy recovery

potential of the materials excavated. Research project

Sin Lin, China

The objectives were for the soil fraction to

be applied as fertiliser, for the residual

inorganic fraction to be used as a source of

energy and to create space for new waste.

General landfill upgrading.

Normandy Landfill,

Beirut, Lebanon For the purposes of land reclamation.

Cancelled (mid-way) due to

political situation.


Appendix 5 – Economic model


Material Revenues and Costs

Revenue / tonne

Material 30% 60% 90% 100% 30% 60% 90% 100%

Glass 4290 8580 12870 14300 £0 £0 £0 £0 £0

Ferrous 6630 13260 19890 22100 £140 £928,200 £1,856,400 £2,784,600 £3,094,000

Aluminium 780 1560 2340 2600 £750 £585,000 £1,170,000 £1,755,000 £1,950,000

Non ferrous 390 780 1170 1300 £2,850 £1,111,500 £2,223,000 £3,334,500 £3,705,000

£2,624,700 £5,249,400 £7,874,100 £8,749,000

Gate fee

RDF 30% 60% 90% 100% RDF Gate Fee (avg of EfW, MBT and RDF export costs)

Plastic 17940 35880 53820 59800 £78.67

Paper and cardboard (P&C) 20670 41340 62010 68900

Leather 6240 12480 18720 20800

Textile 6240 12480 18720 20800

Wood 14040 28080 42120 46800

TOTAL RDF 65130 130260 195390 217100 £17,078,533

% Biomass 72.46%

Gate fee

Landfilled materials 30% 60% 90% 100%

Other 75400

Non MSW 3900

79300 £82.00 £6,502,600.00

Assumptions

Only '100% recovery rate' values used in assessment

Tonnages from 'composition breakdown' table.

WRAP Gate Fee Report 2012 (Scotland Specific Figures where available)

MRF 20

Open Windrow Composting 20

Wood recycling 11

Wood waste to WID compliant facilities -21

EfW (pre-2000 facilities) 64

EfW (post 2000 facilities) 82

MBT 79

Non haz landfill 18

Landfill tax 64

Haz landfill (soil and stones) 29

Haz landfill (construction materials containing asbestos) 30

Current materials recycling (Letsrecycle.com September 2012 and London Metal Exchange)

Mixed plastics 30

Ferrous (Steel can prices) 140

Aluminium (cans) 750

Non Ferrous(based on brass and copper mix) 2850

Glass (-5 to 5 for mixed glass) 0

RDF Costs £/tonne MBT cost?

Gate Fee (EU EfW facility) 55 £79

Baling and wrapping 5

transport 15

TOTAL £75

Revenue per recovery rateTonnes recovered by recovery rate

Tonnes recovered by recovery rate

Tonnes recovered by recovery rate


Energy Revenue

Calculations: electricity revenue

Low High

kg of RDF 1000 1000

MJ/kg 7 20

MJ 7000 20000

MWh in 1.94 5.56

MWh to grid 0.72 2.28

£/tonne 28.78 91.11

Calculations: ROC Revenue

Low High

£25.18 £171.64

Assumptions:

Low High

NCV (MJ/kg) 7 20 AEA Experience

ROC factor (per MWh) 0 2 Min and Max ROC factors (DECC) (only 'high' value used and applied to biomass fraction only)

ROC trading (per MWh) £35 £52 from e-ROC.co.uk

Biomass % 50% 72% High' based on assumed waste composition and 'low' is an AEA assumption

Electricity (per MWh) AEA market knowledge

Efficiency 37% 41% electrical conversion efficiency (%) for Gas Engine (APP Presentation)

£40